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1.
The continuous growing of rice has led to a deterioration in soil quality, resulting in a serious threat to agricultural sustainability in the high rainfall zone of south Gujarat, India. Therefore, crop diversification with a wider choice in the production of crop varieties is being promoted to restore the soil quality. A field experiment was conducted in Navsari, India during 2003–2007 on a Vertisol to evaluate the productivity, sustainability, resource-use efficiency and economics of 10 rice-based cropping systems. The results showed that system productivity for rice–fenugreek (Trigonella foenum-graecum)–okra (Abelmoschus esculentus) was highest (25.73 t ha?1), followed by rice–onion (Allium cepa)–cowpea (Vigna sinensis L.) (24.15 t ha?1); and the lowest system productivity was observed with the rice–wheat (Triticum aestivum)–fallow system (7.85 t ha?1). The sustainable yield index (0.97), production efficiency (102.94 kg ha?1 day?1) and field water use efficiency (15.98 kg ha?1 mm?1) were maximum with the rice–fenugreek–okra system. Similarly, net return (96,286 Rs ha?1), net return per rupee invested (2.83 Rs), monetary production efficiency (385.14 Rs ha?1 day?1) and water use efficiency (59.80 Rs ha?1 mm?1) were maximum with the rice–fenugreek–okra cropping sequence. There were significant effects of various cropping sequences on available nitrogen, phosphorus, potassium and organic carbon content in the soil. Overall, the rice–fenugreek–okra system was found to be the most productive, sustainable, resource-use efficient and remunerative cropping system, followed by the rice–onion–cowpea system.  相似文献   

2.
A field study conducted for three crop years (June?–?July) from 1995?–?96 to 1997?–?98 at the Indian Agricultural Research Institute, New Delhi involving five rice-based cropping systems and six nutrient combinations indicated that rice?–?wheat?–?mungbean (RWM), rice?–?potato?–?mungbean (RPM), rice?–?rapeseed?–?mungbean (RRsM) and rice?–?clover (RC) cropping systems gave 0.7?–?1.0, 3.2?–?5.9, 0.2?–?2.2 and 1.5?–?3.6 t ha?1 yr?1, respectively, higher productivity and removed 7.9?–?22.6, 38.0?–?64.5, 53.0?–?61.8 and 51.4?–?66.1?kg ha?1 yr?1, respectively, more nitrogen, 2.3?–?7.1, 14.5?–?22.8, 3.8?–?7.2 and 17.3?–?21.7?kg ha?1 yr?1, respectively, more phosphorus and 1.6?–?11.4, 15.3?–?42.3, 8.2?–?22.7 and 40.8?–?57.8?kg ha?1 yr?1, respectively, more potassium than the rice?–?wheat (RW) cropping system which led to a net balance of +?151, +?58, ??153 and ??167?kg ha?1 of nitrogen, +?13, ??27, ??8 and ??59?kg ha?1 of phosphorus and ??549, ??551, ??558 and ??691?kg ha?1 of potassium after three cycles of RWM, RPM, RRsM and RC cropping systems, respectively against a net balance of +?201, +?26 and ??533?kg ha?1 of N, P and K, respectively in the RW cropping system. Application of FYM along with NPK in these cropping systems changed the negative balance of nitrogen and phosphorus into positive balance and reduced the negative balance of potassium by 151?–?378?kg ha?1. Application of P and K fertilizers along with nitrogen also helped in arresting the negative balance of P and K under different rice based cropping systems. These results thus indicate that balanced use of NPK and FYM plays a major role for sustaining the productivity of a cropping system.  相似文献   

3.
Field experiments were carried out during rainy (kharif) and winter (rabi) seasons (June–April) of 2008–2010 at Indian Agricultural Research Institute (IARI), New Delhi, to study the productivity, nutrients uptake, iron (Fe) use-efficiency and economics of aerobic rice-wheat cropping system as influenced by mulching and Fe nutrition. The highest yield attributes, grain and straw yields (5.41 tonnes ha?1 and 6.56 tonnes ha?1, respectively) and nutrient uptake in rice was recorded with transplanted and puddled rice (TPR) followed by aerobic rice with Sesbania aculeata mulch. However, residual effect of aerobic rice with wheat straw mulch was more pronounced on yield attributes, grain and straw yields (4.20 and 6.70 tonnes ha?1, respectively) and nutrient uptake in succeeding wheat and remained at par with aerobic rice with Sesbania mulch. Application of iron sulfate (FeSO4) at 50 kg ha?1 + 2 foliar sprays of 2% FeSO4 was found to be the best in terms of all the yield attributes, grain and straw yield (5.09 and 6.17 tonnes ha?1, respectively) and nutrient uptake and remained at par with 3 foliar sprays of 2% FeSO4. Although residual effect of iron application failed to increase the yield attributes, yield and nutrient uptake nitrogen, phosphorus and potassium (N, P, K) except Fe. The highest system productivity, nutrient uptake, gross returns, net returns, B: C ratio and lowest cost of cultivation were recorded with aerobic rice with wheat straw and Sesbania aculeata mulch. Application of FeSO4 at 50 kg ha?1 + two foliar sprays of 2% FeSO4 was found better in respect of system productivity, nutrient uptake, gross returns, net returns, B:C ratio and cost of cultivation in aerobic rice-wheat cropping system. The Fe use efficiency values viz. partial factor productivity (kg grain kg?1 Fe), agronomic efficiency (kg grain increased kg?1 Fe applied), agrophysiological efficiency (kg grain kg?1 Fe uptake), physiological efficiency (kg biomass kg?1 Fe uptake), apparent recovery (%) utilization efficiency and harvest index (%) of applied Fe were significantly affected due to methods of rice production and various Fe nutrition treatments in aerobic rice and aerobic rice-wheat cropping system.  相似文献   

4.
A 2-year field experiment was conducted to assess system productivity, nutrient use efficiency and apparent balances of phosphorus (P) and potassium (K) in diversified rice-based cropping systems at Gazipur, Bangladesh. Four cropping systems: wheat–fallow–rice, maize–fallow–rice, potato–fallow–rice and mustard–fallow–rice in main plots and four nutrient combinations: NPK, NK, NP and PK in sub-plots were arranged in a split-plot design with three replications. Receiving the NPK treatment, all the component crops gave the highest yield, and omission of N from fertilizer package gave the lowest yield. The maize–rice system removed the highest amount of N (217 kg ha?1), P (41 kg ha?1) and K (227 kg ha?1) followed by wheat–rice, potato–rice and the least in mustard–rice system. The wheat–rice and maize–rice system showed negative K balance of –35.5 and –60.4 kg ha?1 in NPK treatment, while potato–rice system showed a positive K balance of 31.0 kg ha–1 with NPK treatment. The N, P and K uptake and apparent recovery by the test crops may be used for site-specific nutrient management. The K rates for fertilizer recommendation in wheat and maize in Indo-Gangetic plain need to be revised to take account for the negative K balance in soil.  相似文献   

5.
A long-term field experiment (1984–2011), was conducted on a Calcic Haploxeralf from semi-arid central Spain to evaluate the combined effect of three treatments: farmyard manure (FYM), straw and control without organic amendments (WOA) and five increasing rates of mineral N on: (1) some energetic parameters of crop production, and (2) the effect of the different treatments on soil organic carbon (SOC) and total N stocks. Crop rotation included spring barley, wheat and sorghum. The energy balance variables considered were net energy produced (energy output minus energy input), the energy output/input ratio and energy productivity (crop yield per unit energy input). Results showed small differences between treatments. Total energy inputs varied from 9.86 GJ ha?1 year?1 (WOA) to 11.14 GJ ha?1 year?1 in the FYM system. For the three crops, total energy inputs increased with increasing rates of mineral N. Energy output was slightly lower in the WOA (33.40 GJ ha?1 year?1) than in the two organic systems (37.34 and 34.96 GJ ha?1 year?1 for FYM and straw respectively). Net energy followed a similar trend. At the end of the 27-year period, the stocks of SOC and total N had increased noticeably in the soil profile (0–30 cm) as a result of application of the two organic amendments. Most important SOC changes occurred in the FYM plots, with mean increases in the 0–10 cm depth, amounting an average of 9.9 Mg C ha?1 (667 kg C ha?1 year?1). Increases in N stocks in the top layer were similar under FYM and straw and ranged from 0.94 to 1.55 Mg N ha?1. By contrast, simultaneous addition of increasing rates of mineral N showed no significant effect on SOC and total N storage.  相似文献   

6.
Conservation agriculture(CA)-based best-bet crop management practices may increase crop and water productivity, while conserving and sustaining natural resources. We evaluated the performance of rainy season maize during 2014 under an ongoing long-term trial(established in 2008) with three tillage practices, i.e., permanent bed(PB), zero tillage(ZT), and conventional tillage(CT) as main plots, and four intensified maize-based cropping systems, i.e., maize-wheat-mungbean, maize-chickpea-Sesbania(MCS), maizemustard-mungbean, and maize-maize-Sesbania) as subplot treatments. In the seventh rainy season of the experiment, maize growth parameters, yield attributes, yield, and water-and energy-use efficiency were highest at fixed plots under ZT. Maize growth parameters were significantly(P 0.05) superior under ZT and PB compared with CT. Maize yield attributes, including cobs per m~2(7.8), cob length(0.183 m), grain rows per cob(13.8), and grains per row(35.6), were significantly higher under ZT than CT; however, no significant effect of cropping systems was found on maize growth and yield attributes. Zero tillage exhibited the highest maize productivity(4 589 kg ha~(-1)). However, among the cropping systems, MCS exhibited the highest maize productivity(4 582 kg ha~(-1)). In maize, water use was reduced by 80.2–120.9 mm ha-1under ZT and PB compared with CT, which ultimately enhanced the economic water-use efficiency by 42.0% and 36.6%, respectively. The ZT and PB showed a 3.5%–31.8% increase in soil organic carbon(SOC) at different soil depths(0–0.45 m), and a 32.3%–39.9% increase in energy productivity compared with CT. Overall, our results showed that CA-based ZT and PB practices coupled with diversified maize-based cropping systems effectively enhanced maize yield and SOC,as well as water-and energy-use efficiency, in northwestern India.  相似文献   

7.
System of Rice Intensification (SRI) has spread as an innovation of rice cultivation that can produce higher crop yields and conserve seed and water resources. The SRI innovation is also gaining popularity in north-western (NW) Himalayas on one hand and hybrid rice technology on the other in the region. Moreover, rice productivity in NW Himalayas is quite low owing to the use of low-yielding germplasm and poor crop management. Thus, SRI principles coupled with hybrid rice technology seems to be a boon to boost rice productivity in the irrigated ecosystem of wet-temperate NW Himalayas well known for rice cultivation. Therefore, comparative performance of promising rice hybrids under SRI was assessed at three locations in wet-temperate NW Himalayas (India) using nine promising rice hybrids including state-recommended rice hybrid “Arize–6129” as check cultivar. It was revealed that various hybrids differed significantly w.r.t. days to 50% flowering, days to 75% maturity, plant height, tillers hill?1, panicles hill?1, panicles m?2, and panicle length. Highest number of panicles m?2 (370) was observed in Arize–6129 followed by US–312, Bioseed–786, and NK–3325, respectively. Significantly longer panicles were observed in Dhanya–2366 followed by Arize–6129, US–312, Bioseed–786, NK–3325, and US–10, respectively. Arize–6129 resulted in significantly higher grain (75 q ha?1) and straw yield (125 q ha?1) followed by US–312, Dhanya–2366, NK–3325, PAC–801, US–10, Bioseed–786, Uday–111, and Uday–131, respectively. The production- and monetary-efficiency as well as gross and net returns and B:C ratio also followed the similar trend as that of crop productivity with significantly higher production– (67 kg ha?1 day?1) and monetary–efficiency (INR 608.4 ha?1 day?1), and net returns (INR 68138 ha?1) and B:C ratio (3.66) in check cultivar “Arize–6129” over other rice hybrids. Higher grain productivity (49.5–75.0 q ha?1), net returns (INR 39238–68138 ha?1), and B:C ratio (2.53–3.66) in current study conclusively inferred that SRI coupled with hybrid rice technology can harness higher productivity and profitability. Protein content (8.30–8.45%) exhibited higher values under Bioseed–786 followed by NK–3325, UDAY–111, and Arize–6129; however, NPK uptake (grains, straw, total) was significantly highest in Arize–6129 followed by US–312, Dhanya–2366, and NK–3325, respectively. Total water productivity (6.4–9.75 kg ha?1 mm?1), irrigation water productivity (16.5–25 kg ha?1 mm?1), and economic water productivity (64.0–97.5 INR ha?1 mm?1) collectively followed the trend of Arize–6129 > US–312 > Dhanya–2366 > NK–3325 > US–10 > PAC–801 > Bioseed–786 > Uday–111 > Uday–131 in current study. Overall, Arize–6129, US–312, and Dhanya–2366 were proved as potential rice hybrids in terms of their higher crop and water productivity and economic profitability among above nine rice hybrids for their large-scale cultivation under SRI in wet-temperate NW Himalayas.  相似文献   

8.
An experiment was conducted at ICAR Research Complex for Eastern Region, Research Farm, Sabajpura, Patna (longitude 85°13′N and 1atitude 25°37′E), Bihar, India for four consecutive years 2004–05 to 2007–08 to develop a diversified cropping system for an irrigated ecosystem in Bihar by introducing pulse/oilseed/vegetables as a second or third crop in 10 rice-based cropping systems. Four crop cycles have been completed for all the cropping systems. During all years of the experiment there were significant variations among the cropping systems. Maximum paddy yield equivalent was recorded in rice–tomato–bottle gourd (40.44 t ha?1) followed by rice–potato–onion (28.47 t ha?1), rice–coriander–lady's fingers (26.79 t ha?1), rice–carrot–cowpea (24.59 t ha?1) and rice–mustard–tomato (24.44 t ha?1). A higher value for the diversification index (DI) represents a higher level of crop diversification. It is evident from the results, that DI varies from 0.299 on a medium-sized farm to 0.903 on a small farm, with an average DI value of 0.643 among all farm categories. A survey revealed that the average DI value for small-scale farmers was highest (0.741) compared with the medium- (0.591) and large-scale (0.626) categories, and the differences were negligible. This seems reinforce the view that the smaller the farm, the higher the level of crop diversification.  相似文献   

9.
《Biosystems Engineering》2002,81(3):347-354
One requirement for an oilseed crop to be considered for biodiesel production is that it provides a positive energy return compared with the energy used to produce the fuel. This in part depends on the energy input for the oilseed production. This paper studies the energy balance between the input and the output per unit area for a sunflower crop grown in Greece, in order to evaluate it as a source for biodiesel production. Calculation of the energy input was based on the operations and various inputs as used by farmers in Evros in the north of Greece. To estimate the energy required to produce the sunflower seeds, to manufacture fertilizers and pesticides and to produce and use the farm machinery, appropriate energy equivalents from the literature were taken into account. The energy outputs were estimated by simply multiplying the yield of sunflower seeds and stems by their corresponding energy value. The total energy input was calculated to be 10·49 GJ ha−1, with fertilizers being the major inputs. Assuming a typical sunflower seed yield of 1800 kg ha−1, as obtained under normal conditions on fertile drylands, and taking into account the energy value of the seed, the net energy value was estimated to be 36·87 GJ ha−1 and the ratio of energy outputs to energy inputs approximately 4·5:1.  相似文献   

10.
ABSTRACT

Soil fertility and water use are two important aspects that influence rice productivity. This study was conducted to evaluate the performance of in-situ (sesbania and rice bean) and ex-situ (subabul) green manuring along with zinc fertilization on water productivity and soil fertility in rice under rice–wheat cropping system at Indian Agricultural Research Institute, New Delhi, India. Sesbania incorporation recorded higher total water productivity (2.20 and 3.24 kg ha?1 mm?1), available soil nutrients, organic carbon, alkaline phosphatase activity, microbial biomass carbon and increased soil dehydrogenase activity by 39.6 and 26.8% over subabul and rice bean respectively. Among interaction of green manures and zinc fertilization, subabul × foliar application of chelated zinc-ethylenediaminetetraacetic acid at 20, 40, 60 and 80 days after transplanting recorded highest total water productivity (2.56 and 3.79 kg ha?1 mm?1). Foliar application of chelated Zn-EDTA at 20, 40, 60 and 80 days after transplanting recorded significantly higher water productivity than other Zn treatments, however it was statistically similar with foliar application of zinc at active tillering + flowering + grain filling. Sesbania × 5 kg Zn ha?1 through chelated Zn-EDTA, recorded highest available nitrogen, phosphorus, potassium, zinc, manganese, copper and iron than other green manure and Zn fertilization interactions, although it was statistically similar with rice bean × 5 kg Zn ha?1 through chelated Zn-EDTA as soil application. Sesbania × foliar application of 5 kg Zn ha?1 through chelated Zn-EDTA as soil application recorded highest soil enzymatic activities and microbial biomass carbon.  相似文献   

11.
Field experiments were conducted during spring–rainy (kharif) seasons of 2005 and 2006 on a sunflower–mungbean cropping system at the research farm of the Division of Agronomy, Indian Agricultural Research Institute (IARI), New Delhi, India. The objectives of this study were to investigate the residual effect of nitrogen sources, sulfur and boron levels applied to sunflower on productivity, nutrient concentrations and their uptake by the succeeding mungbean crop in a sunflower–mungbean cropping system. The experiment with 19 treatments was laid out in factorial randomized block design for both sunflower and mungbean. The residual effects of nutrients applied to sunflower were significant on the succeeding mungbean crop in terms of biometric parameters, yield attributing characters, seed yield and soil nutrient status. The highest mungbean seed yield (961.2 kg ha?1) was produced with 50 kg ha?1 sulfur application to the preceding sunflower crop, which was significantly (p < 0.05) higher than with 0 and 25 kg sulfur ha?1. The concentrations and uptake of nitrogen, sulfur and boron were also greater in the succeeding mungbean crop due to the residual effects of nutrients applied to the preceding sunflower crop. The soil nutrient status before and after mungbean indicated that the available nitrogen and sulfur were higher due to application to the preceding crop, while available boron after mungbean was even higher than after sunflower due to its slow release and static nature in the soil.  相似文献   

12.
A comprehensive long-term study (2006–2010) was undertaken to develop a balanced and integrated nutrient supply system for sunflower-based cropping sequence considering the efficient utilization of residual and cumulative soil nutrient balance along with added fertilizers by the crops grown in rotation. The fertilizer application was done in potato and sunflower while greengram was raised as such on their residual effect. Significant response in yield was observed with 150% of the recommended nitrogen, phosphorus and potassium (NPK) or inclusion of farmyard manure (FYM) with the recommended NPK in the cropping sequence indicating 6.2–7.0% gain in system productivity over the existing recommendations. Each additional unit of P and K nutrition prompted system productivity by 18.9 and 11.0 kg kg?1 of applied nutrient, respectively. Apparent yield decline was observed in K and PK omission plots to the extent of 15.8 and 27.4% in potato, 10.5 and 23.9% in sunflower and 4.2 and 8.3% in greengram, respectively, compared to the recommended fertilization. The superiority of the FYM along with the recommended NPK (potato/sunflower) was evident on the overall profitability and sustainability of the system, highlighted by the significantly higher productivity (7.16 t SFEY ha?1), sustainability yield index (SYI; 0.76), production efficiency (PE; 27.85 kg SFEY ha?1 day?1) and net returns (2520 USD ha?1) with a B:C ratio of 2.91. Apparent change in potassium permanganate (KMnO4)-N was negative in all the treatments while N and P balance was positive with 150% NPK fertilization. Nutrient uptake exceeded the replenishment with 100% NPK application and maintained net negative soil nutrient stock for all the primary nutrients, indicating the need for revalidation of the existing recommendations in the system perspective. Conspicuous improvement in residual soil fertility in terms of maximum buildup of soil organic carbon (14%) and enhancement in soil KMnO4-N (4.2%), Olsen-P (19.4%), ammonium acetate (NH4OAc)-K (5.8%) and dehydrogenase enzyme activity (44.4%) was observed in FYM-treated plots over the initial values. The study suggested that the inclusion of legumes and FYM application with the recommended NPK in potato-sunflower cropping sequence will sustain the system’s productivity through the efficient use of nutrients, enhanced microbial activity and improved soil health while combating escalating prices of fertilizers as well as environmental issues in the Indo-Gangetic plains of India and similar environments.  相似文献   

13.
ABSTRACT

Lack of crop diversification with suitable vegetable-based cropping system is a major constraint in limiting the productivity and sustainability of north-western Indian sub-Himalayas. To find out a sustainable vegetable-based cropping system in this region, a three year colocasia-based vegetable intensive experiment was conducted at Hawalbagh, Almora, India in a sandy clay loam soil under sub-temperate climatic conditions. Seven colocasia-based vegetable cropping systems along with rice–wheat system were compared under recommended package and practices. The system productivity in terms of colocasia equivalent yield was highest under colocasia–onion–frenchbean (52.38 Mg ha?1) system. Sustainable yield index was highest with colocasia–gardenpea–frenchbean system (0.86). After 3 years, total soil organic carbon (0–5%), available N (2–22%), P (–7% to 14%) and K (3–15%) concentrations were increased in all cropping systems except rice–wheat system, where negative balance of available P (7%) was observed over that of initial soil. Significantly higher soil microbial activity, soil carbohydrate, dehydrogenase, protease, acid and alkaline phosphatases activity were observed under colocasia–onion system. The results suggest that colocasia–onion–frenchbean system with higher productivity improves soil fertility and enhances enzymatic activities.  相似文献   

14.
Zinc (Zn) fertilization is important for Zn crop biofortification as well as increasing yields, thus proper Zn recommendations for soil application is needed for Zn deficient soils. The effectiveness of Zn applications was evaluated in different combinations of rates (2.5, 5.0, 7.5, and 10.0?kg?ha?1 per year) and frequencies (initial, alternate, and every year) in rice (Oriza sativa L.) – wheat (Triticum aestivum L.) cropping system in a Zn-deficient upland calcareous soil in the fourth year. Zn applications to rice at 7.5 and 10?kg?ha?1 of alternate year and 5.0 to 10?kg?ha?1 of every year had the highest rice equivalent yield as compared to no-Zn treatment. Hence, Zn application to rice at 7.5?kg?ha?1 at alternate years is the lowest rate at which highest rice equivalent yield of rice-wheat cropping system can be obtained.  相似文献   

15.
Field experiments were conducted at the Indian Agricultural Research Institute, New Delhi, India for three years from 2001–2002 to 2003–2004 to study the relative efficiency of diammonium phosphate (DAP) and mussoorie rock phosphate (MRP) in a rice-potato-mungbean cropping system. Phosphorus application significantly increased productivity, protein yield and energy output of rice-potato-mungbean cropping system and resulted in an increase in 0.5 M sodium bicarbonate (NaHCO3) extractable phosphorus (P) content in soil. The MRP at 35 kg P ha?1 was at par with 17.5 kg P ha?1 as DAP in terms of productivity, protein yield, and energy output but significantly superior in terms of PSB population in soil. Phosphorus balance (application – crop removal) was generally more positive for MRP than DAP and the highest with an application of 52.5 kg P ha?1 as MRP. Present study indicates that P requirement of a rice-potato-mungbean cropping system can be met with 76–79% higher dose of MRP as compared to DAP.  相似文献   

16.
The rice–wheat cropping system (RWCS), producing about 5–10 Mg ha–1 y–1 of grain, is the backbone of food‐crop production in South‐East Asia. However, this system shows signs of fatigue as indicated by declining yields, negative nitrogen (N) balances, and reduced responses to applied fertilizer at some research centers. The return of rice and wheat residues can recycle up to 20%–30% of the N absorbed by the crops. However, their wide C : N ratio can temporarily immobilize native and applied N. To overcome this immobilization, wheat‐straw application was supplemented with the incorporation of Sesbania green manure and mungbean residues, and their effects on productivity, agronomic N efficiency, and system's apparent N balances were studied. Combining the application of wheat straw with Sesbania green manure or mungbean residues increased cereal grain yield and agronomic N efficiency and improved the generally negative apparent N balances. The combined use of wheat straw and mungbean produced an additional 0.5–0.6 t ha–1 protein‐rich grain and thus appears to be the most promising residue‐management option for rice–wheat cropping systems in South Asia, provided that the transition cropping season between wheat harvest and rice transplanting is long enough.  相似文献   

17.
The objective of the study was to determine the profitability and employment-generation potential of different cropping systems involving menthol mint (Mentha arvensis L.) as a component of sequential/intercropping in comparison with the most common paddy–wheat–green gram cropping system. Field experiments were conducted at Lucknow, India (26° 5′ N, 80° 5′ E and 120 m above mean sea level) for three years from July 2004 to June 2007. Menthol mint yielded the maximum fresh shoot biomass and essential oil (21.0 t and 151 kg ha?1, respectively) grown after sweet basil (Ocimum basillicum)–potato followed by paddy–potato–menthol mint (18.9 t and 136 kg ha?1, respectively) and maize–mustard–menthol mint (17.7 t and 131 kg ha?1, respectively). Net returns of all the menthol-mint-based cropping systems were 82.6–354% higher than traditional paddy–wheat–green gram cropping system. Maize–garlic–menthol mint + okra was found to be most profitable (77,200 Rs ha?1) followed by pigeon pea + sweet basil–menthol mint + okra (76,120 Rs ha?1). Employment-generation efficiency was much higher in cropping systems involving menthol mint and vegetable crops, the highest (2.21 man days ha?1 day?1) being in a maize–cauliflower–onion–menthol mint + okra cropping system.  相似文献   

18.
A long-term field experiment with rice-wheat cropping was started in the wet season of 1988 with four levels of lantana (Lantana camara L.) (0, 10, 20, and 30 Mg ha?1 on fresh weight basis) and three tillage practices (No puddling, puddling, and soil compaction). From wet season of 1997, however, three tillage practices were replaced with three levels of nitrogen (N) and potassium (K) to rice (33, 66, and 100% of recommended) and 66% of recommended N, phosphorus (P), and K to wheat. Phosphorus was totally omitted for the rice crop. The recommended N and K for rice was 90 and 40 kg ha?1, whereas the recommendations for N, P, and K for wheat were 120, 90 and 30 kg ha?1. Organic amendments are known to improve soil productivity under rice-wheat cropping by improving physical conditions and nutrient status of the soil, but their availability is restricted. There is a need to identify locally available and cost-effective organic materials that have minimal alternate uses as fodder and fuel. We evaluated Lantana camara L. residues, a fast-growing weed in nearby wastelands, as a potential soil organic amendment. Among the different fractions of K, nonexchangeable K was dominant followed by exchangeable and water soluble K. The incorporation of lantana (10 to 30 Mg ha?1) over the last 12 years has resulted in a significant build-up of all the K fractions, the maximum being in water-soluble K (10 to 32%) followed by exchangeable K (18 to 27%) and least in nonexchangeable K (5 to 7%) over no lantana incorporation. The increasing levels of these two inputs significantly and consistently increased ammonium acetate (NH4OAc)- extracted K (available K) content in soil and also resulted in significantly higher accumulation of K by the crops during the years of experimentation. Among different K fractions, exchangeable K was observed to be the most important K fraction contributing towards wheat and rice yields as well as K accumulation by wheat and rice. Stepwise multiple regression equations indicated that exchangeable K was the most important variable contributing towards total variation in grain yield and K accumulation by wheat or rice.  相似文献   

19.
Foliar fertilization may be a viable strategy to boron supply in irrigated cropping systems with common beans (Phaseolus vulgaris), since it prevent B leaching. The aim of this work was to evaluate the economic viability and physiological parameters of the common beans production in irrigated cropping systems using sources and increasing foliar boron doses. A field experiment was carried out using an experimental block design in a factorial scheme 2?×?5?×?3, with two sources of B (boric acid and borax) and five doses: 0 (control), 2, 4, 6 e 8?kg?ha?1, with three repetitions. Foliar B applications were performed at 40 days after seeds germination, in pre-flowering stage. Physiological process (transpiration, stomatal conductance, CO2 internal concentration, net photosynthesis, and relative chlorophyll index), B level in leaves and grain yield were measured. These data were used to determine the economic viability of B fertilization in common beans. Both boric acid and borax increased B levels in common beans leaves. Borax affected some physiological process reducing stomatal conductance and increasing net photosynthesis. Using borax, the highest net photosynthesis was observed at a rate of 4?kg?ha?1, while the boric acid increased net photosynthesis linearly after increasing B doses application. An enhance of 311?kg?ha?1 in the grain yield was observed using borax related to the control (without B application); however, grain yield decreased linearly after application of increasing B doses, as boric acid. Comparing the economic viability of sources and doses of B, the highest profitability is obtained using borax at a rate of 4?kg?ha?1, which promoting a differential profit of US$534.44 per hectare compared to common beans cropping without B.  相似文献   

20.
The environmental and economic consequences of nitrogen (N) lost in rice-based systems in Vietnam is important but has not been extensively studied. The objective of this study was to quantify the amount of N lost in major cropping systems in the Red River Delta. An experiment was conducted in the Red River Delta of Vietnam, on five different crops including rose, daisy, cabbage, chili, and a rice–rice–maize rotation during 2004 and 2005. Core soil samples were taken periodically in 20-cm increments to a depth of 1 m and analyzed for nitrate–nitrogen and ammonium–nitrogen. The results indicate appreciable leaching losses on N in high-rainfall and irrigation conditions, especially when fertilizer application was not well synchronized with crop N demand. Highest annual leaching losses of N were recorded in flowers with 185–190 mm of percolation and 173–193 kg N ha?1, followed by vegetable (cabbage and chili) with 120–122 mm of percolation and 112–115 kg N ha?1, while it was lowest in rice with about 50 kg N ha?1. We developed a simple N transport model that combined water and N movement through the soil profile. In most cases, the model accurately predicted the seasonal dynamics of N as well as N flow between soil layers and the amounts of N lost from the soil profile. The simulated results of N leaching with soil “puddling” conditions illustrate the advantage of an impermeable or hardpan layer in increasing water and nutrient use efficiencies in these soils. These model results also showed that it is possible to accurately estimate N losses with only a few parameters and helped us identify the risks of N leaching.  相似文献   

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