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1.
Irrigated cotton in the tropical dry season. I: Yield,its components and crop development 总被引：1，自引：0，他引：1
Growing cotton during the dry (winter) season avoids many insect pests endemic in the wet season (summer) and could permit the reintroduction of cotton to the semi-arid tropics in Australia. This research addressed the questions: (1) what yield is possible given the lower mid-season radiation and temperature of the dry season, (2) the prediction and management of crop development using a range of sowing months to assess whether cotton can be grown and picked within the dry season. Over three seasons two Gossypium hirsutum L. (upland) cultivars and one Gossypium barbadense L. cultivar were sown from March, to June at the Ord River (15.5°S) in Western Australia. For the upland cultivars, lint yields of 1900–2300 kg/ha for March and April sowings were at the high end of Australian and International benchmarks. High lint yields were linearly correlated with a greater proportion of bolls that were located on outer sites on fruiting branches than for high yielding crops in temperate climates (∼30°lat.). The change in boll position increased the length of the growing season which was also linearly correlated with yield. Future research needs to confirm if low minimum temperatures early in flowering caused the change in boll position and to measure the impact of extreme temperature seasons on yield and time to maturity. The lint yield of the G. barbadense cultivar was highest at a March sowing, at least 87% of the upland cultivars, which is comparable with temperate climates. The frequency of temperatures >35 °C and <11 °C affected time to squaring, requiring modification of existing development models derived in temperate climates. It was concluded sowing during March to April should achieve the dual objectives of high yields and avoidance of rain at maturity. The wide temperature range observed in these experiments improved the prediction of boll period from mean temperature; this function should be applicable outside the semi-arid tropics. 相似文献
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《Field Crops Research》2005,93(1):74-84
Seedling transplanting and plastic mulching are widely adopted intensive planting systems in cotton production in China. Manual removal of early- or late-season flowers may improve seed quality without sacrificing yield through the compensatory growth of cotton plants. Two experiments were conducted, in Yellow River Valley in China from 2002 to 2003, to test if the intensive systems and flower removal can be used for enhancing hybrid seed production. Results in the first experiment show that yields of seed cotton and seed, and seed quality parameters averaged across three plant densities (2.25, 3.00 and 3.75 plants/m2), were significantly improved by either transplanting or plastic mulching relative to conventional planting. The improvements in yield and quality in two intensive planting systems were mainly attributed to longer and earlier flowering period. Transplanted plants did not differ significantly from mulched plants in seed yield, seed maturity and percentage germination, but transplanting decreased lint percentage and increased seed index relative to mulching. In terms of seed yield and quality, the optimum plant density for each planting system was 3.00 plants/m2. At the optimum plant density, seed yields averaged across two years for transplanting and mulching systems were 31.3% and 32.6% higher than for conventional planting system, respectively. Flower removal did not significantly affect seed yield, but removal of late-season or both early- and late-season flowers significantly improved seed quality. It was concluded that transplanting or plastic mulching, low plant density (3.00 plants/m2), and removal of late-season or both early- and late-season flowers can be integrated to enhance yield and quality of hybrid seed of cotton. 相似文献
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A field study was carried out to quantify the compensation capacity of Bacillus thuringiensis (Bt)-transgenic cotton to simulated damage by manually removing squares during the early growing season in 2004 and 2005 in combination with CO2 levels (ambient CO2 and elevated CO2). Treatments included: initial squares were wholly (100%) removed manually for 1 week (i.e., SR1 treatment) and for 2 consecutive weeks (i.e., SR2 treatment). Plant leaf area was measured every 2 weeks, and plant root, stem, leaf, shatters, boll dry weight and lint yield and maturity were measured at harvest. Significantly higher leaf area per plant was observed on each sampling date for SR1 and SR2 treatments compared with control (SR0) treatment in 2004 and 2005 under elevated CO2. Significantly higher lint yield and maturity were observed for SR0, SR1 and SR2 treatments under elevated CO2 in 2004 and 2005. CO2 concentration and square removal significantly affected plant lint yield and maturity. Moreover, the interaction between CO2 concentration × square removal had a significant effect on plant leaf dry weight, lint yield and maturity. Our results indicated that transgenic cotton plants can compensate for the manual removal of 100% of the initial squares for 1 and 2 weeks under ambient and elevated CO2. 相似文献
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As the most important cultural practices for cotton production, the single effects of plant density and [nitrogen (N) and potassium (K)] fertilization on yield and yield components are well documented but their combined effects on Bt cotton are poorly understood. Using a split–split plot design with four replications, we conducted a two-year field experiment in two fields, one with lower fertility and the other with higher fertility, in the Yellow River Valley of China. The aim was to evaluate both the individual and combined effects of plant density and nitrogen and potassium fertilization on yield, yield components and uptake of major nutrients. The main plots were assigned to plant density (4.5 and 7.5 plants/m2), while nitrogen (0 and 240 kg N/ha) and potassium fertilization (0 and 150 kg K/ha) were assigned to the sub- and sub–subplots. Lint yield was improved with high plant density (7.5 plants/m2) in the lower fertility field, particularly without N and K application, but not in the higher fertility field. Nitrogen or K application also increased lint yield, and a combination of high plant density, N and K application further improved lint yield in the lower fertility field, while only K application increased lint yield in the higher fertility field. Lint percentage was not affected by any of the variables studied. Thus, the yield increase due to plant density, fertilization or their combinations was attributed to increases in boll number or boll weight. The ratio of seed cotton to stalk (RSS) was linearly correlated with harvest index, and thus can be a simple indicator of dry matter allocation to reproductive structures. Increased yield due to plant density and fertilization was mainly attributed to the enhanced biological yield in the lower fertility field, while the yield increase due to K fertilization was mainly due to increased RSS in the higher fertility field. The plants used approximately equal N and P to produce 100 kg lint in both fields, but the uptake of K to produce 100 kg lint in the higher fertility field was about 21% more than that in the lower fertility field. Ratios of N:P:K were 1:0.159:0.604 in the lower fertility field and 1:0.159:0.734 in higher fertility field. This study suggests that K fertilization was extremely important for maintaining high yield, although luxury consumption occurred in the higher fertility field; N was applied more than required in the highly fertile field, and increased plant density would be beneficial to cotton yield in the lower fertility field. 相似文献
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Plastic film mulching is an effective practice to improve water harvest and crop productivity in semiarid areas. The grain yield of maize (Zea mayis) as affected by various mulching practices was studied in the field in 2006 and 2007 to determine a mulching pattern that would increase rainwater harvest and crop yield. In 2006, three treatments were used: (1) flat plot without mulch (CK); (2) two ridges and furrows mulched by one plastic film and maize planted in the furrow between the two ridges (DRM); (3) two rows of maize planted in a ridged bed mulched with plastic (RM). Two additional treatments were tested in 2007: (4) two rows of maize mulched with a 70-cm wide plastic film and then 30 cm of bare soil alternated (NM); (5) maize planted without ridges in double rows 80 cm apart and the whole plot mulched with plastic film (WM). Maize yield was highest in the DRM treatment: 1150 kg ha−1 in 2006 and 6130 kg ha−1 in 2007. This was associated with better topsoil moisture in the planting zone and higher soil temperature in the DRM treatment compared with the other treatments. The soil moisture in DRM reached 10.5% and 22.6%, in 2006 and 2007, respectively, the highest of all the treatments. The mean temperature in DRM was higher than in CK and RM by 1.2 °C and 0.4 °C, respectively in 2006, while in 2007, it was higher than that in CK by 3.1 °C, in RM by 0.6 °C, in NM by1.7 °C and in WM by 0.6 °C in 2007. The higher temperatures in the DRM treatments resulted in the maize maturing earlier than in the other mulched treatments, 15 days earlier than in RM in 2006 and 11 days, 3 days, and 14 days earlier than in RM, WM, and NM, respectively in 2007. The highest water-use efficiency (WUE) was found in DRM in both years. In 2006, the WUE in DRM was six times greater than that in CK and 9.96% greater than in RM. In 2007, the WUE for grain in the DRM treatment was 16.6 kg ha−1 mm−1, 11 times greater than that in CK and greater than RM, NM and WM by 67.7%, 26.7% and 9.2%, respectively. It is concluded that the double ridges and furrow mulching treatment could serve as a model for maize production for small-holder farmers in semiarid regions. 相似文献
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Jadwiga Andrzejewska Katarzyna SadowskaSebastian Mielcarek 《Industrial Crops and Products》2011,33(2):462-468
In the moderate climate of Poland it is recommended that milk thistle (Silybum marianum L. Gaertn.) be grown on fertile soils. The plant, however, develops a strong root system, so a working hypothesis has developed that cultivation can be extended to light soils with periodic water deficits. The aim of the present research was to determine the effects of sowing milk thistle on light soil at different dates and rates on the achene yield and flavonolignan content. This experiment was carried out during 2004-2006 at the Mochelek Experiment Station of the University of Technology and Life Sciences in Bydgoszcz (53°13′ N; 17°51′ E). The average fruit yields were 1.23 t ha−1; those of silymarin were 26.5 kg ha−1. The moisture and thermal conditions during the research years caused the fruit yields to range from 0.55 to 1.68 t ha−1 and silymarin yields from 13.3 to 35.4 kg ha−1. Delaying sowing from early to mid-April increased the plant density and decreased numbers of inflorescences and fruits per inflorescence; as a result, no effect of sowing date on fruit yield was found. Delaying the sowing date increased silymarin content by about 0.4% and its yield by 5.3 kg ha−1. Increasing the sowing rate from 12 to 24 kg ha−1 resulted in a slight (40 kg ha−1) but significant increase in achene yield; however, it did not affect the silymarin content. The average silymarin content in fruits was 2.18%. The ratio of silydianin to silychristin was 1:2.2, and the ratio of silydianin to the sum of silybinin and isosilybinin was 1:3.3. 相似文献
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陆地棉品种间杂种主要性状的遗传相关和通径分析 总被引：6，自引：0，他引：6
研究了陆地棉品种问杂种F1代主要经济性状间的相互关系．并对皮棉产量、纤堆长度和霜前花率等3个目标性状进行了遗传通径分析。结果表明，单铃重与皮棉产量遗传相关最密切，对皮棉产量的直接遗传正效应也最大；纤堆长度与霜前花率遗传正相关最密切，而对纤维长度的直接遗传正效应最大的则是皮棉产量；霜前花率与单铃重遗传正相关最密切，对霜前花率直接遗传正效应最大的是衣指。通过研究提出高产、优质、早熟性的杂种F1代选育的主攻方向是以抗病性为前提．首抓铃重，次抓衣指。 相似文献
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Plant available soil water at sowing in Mediterranean environments—Is it a useful criterion to aid nitrogen fertiliser and sowing decisions? 总被引：1，自引：0，他引：1
In regions where rainfall is low and variable, water stored in the soil profile prior to sowing can alter yield expectation and hence management decisions. Thus, wheat farmers in Mediterranean regions may be able to benefit from knowing the amount of soil water at sowing by optimising their nitrogen (N) fertiliser management and by deciding on whether or not to sow a crop. We used the ASPIM-Nwheat model to explore how levels of plant available soil water (PAW) at sowing, N fertiliser rate, soil, site and season-type (below or above median rainfall) affected wheat yields at sites in the Mediterranean area of southwest Australia. Overall, the greatest influence on yield potential and the consequent N fertilisation requirement was season-type. The additional yield per mm PAW at sowing was generally higher in seasons with below median rainfall, except when yields were severely water-limited by below median rainfall of <222 mm combined with <40 mm PAW at sowing on light clay soil with 109 mm plant available water capacity (PAWC). Sowing was generally warranted; only on light clay soil with <10 mm PAW at sowing and below median rainfall of <222 mm was there an opportunity for a conditional sowing strategy. Scope for varying N fertiliser rates with PAW at sowing was limited to soils with higher PAWC (109 and 130 mm, respectively) in below median rainfall seasons at the wetter site (295 mm mean seasonal rainfall), and in both season-types at the drier site (225 mm mean seasonal rainfall). Only in these combinations, soil water at sowing modified the optimal N fertiliser rate for maximum average yield resulting in significant interactions between PAW at sowing and N fertiliser rates. Similar interactions were found for a site in the Mediterranean Basin and a site in the eastern Australian subtropics on soil with high PAWC (183 and 276 mm, respectively). In contrast, there was no benefit from modifying crop management based on PAW at sowing on soil with low PAWC (i.e. sandy soil) and/or under conditions of high in-season rainfall. The conditional N management approach becomes more viable as the proportion of water stored in the soil prior to sowing increases relative to total crop water use and as the PAWC of the soil increases. Knowledge of PAW at sowing × N fertiliser rate interactions in a particular soil × site × season-type context can help to identify sites where a more targeted N management dependent on amounts of PAW at sowing is potentially profitable. 相似文献
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Yield, grain quality and water use efficiency of rice under non-flooded mulching cultivation 总被引：9，自引：0，他引：9
Plastic film or straw mulching cultivation under non-flooded condition has been considered as a new water-saving technique in rice production. This study aimed to investigate the yield performance in terms of quality and quantity and water use efficiency (WUE) under such practices. A field experiment across 3 years was conducted with two high-yielding rice cultivars, Zhendao 88 (a japonica cultivar) and Shanyou 63 (an indica hybrid cultivar) and four cultivation treatments imposed from transplanting to maturity: traditional flooding as control (TF), non-flooded plastic film mulching (PM), non-flooded wheat straw mulching (SM), and non-flooded no mulching (NM). Compared with those under the TF, root oxidation activity, photosynthetic rate, and activities of key enzymes in sucrose-to-starch conversion in grains during the grain filling period were significantly increased under the SM, whereas they were significantly reduced under the PM and NM treatments. Grain yield showed some reduction under all the non-flooded cultivations but differed largely among the treatments. The reduction in yield was 7.3–17.5% under the PM, 2.8–6.3% under the SM, and 39–49% under the NM. The difference in grain yield was not significant between TF and SM treatments. WUE for irrigation was increased by 314–367% under the PM, 307–321% under the SM, and 98–138% under the NM. Under the same treatment especially under non-flooded conditions, the indica hybrid cultivar showed a higher grain yield and higher WUE than the japonica cultivar. The SM significantly improved milling, appearance, and cooking qualities, whereas the PM or the NM decreased these qualities. We conclude that both PM and SM could significantly increase WUE, while the SM could also maintain a high grain yield and improve quality of rice. The SM would be a better practice than the PM in areas where water is scarce while temperature is favorable to rice growth, such as in Southeast China. 相似文献
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Xiaobin Wang Kuai Dai Dingchen Zhang Xiaoming Zhang Yan Wang Quansheng Zhao Dianxiong Cai W.B. Hoogmoed O. Oenema 《Field Crops Research》2011
Rainfed crop production in northern China is constrained by low and variable rainfall. This study explored the effects of tillage/crop residue and nutrient management practices on maize (Zea mays L.) yield, water use efficiency (WUE), and N agronomic use efficiency (NAE) at Shouyang Dryland Farming Experimental Station in northern China during 2003–2008. The experiment was set-up using a split-plot design with 3 tillage/crop residue methods as main treatments: conventional, reduced (till with crop residue incorporated in fall but no-till in spring), and no-till (with crop residue mulching in fall). Sub-treatments were 3 NP fertilizer rates: 105–46, 179–78 and 210–92 kg N and P ha−1. Maize grain yields were greatly influenced by the growing season rainfall and soil water contents at sowing. Mean grain yields over the 6-year period in response to tillage/crop residue treatments were 5604, 5347 and 5185 kg ha−1, under reduced, no-till and conventional tillage, respectively. Grain yields under no-till, were generally higher (+19%) in dry years but lower (−7%) in wet years. Mean WUE was 13.7, 13.6 and 12.6 kg ha−1 mm−1 under reduced, no-till, and conventional tillage, respectively. The no-till treatment had 8–12% more water in the soil profiles than the conventional and reduced tillage treatments at sowing and harvest time. Grain yields, WUE and NAE were highest with the lowest NP fertilizer application rates (at 105 kg N and 46 kg P ha−1) under reduced tillage, while yields and WUE tended to be higher with additional NP fertilizer rates under conventional tillage, however, there was no significant yield increase above the optimum fertilizer rate. In conclusion, maize grain yields, WUE and NAE were highest under reduced tillage at modest NP fertilizer application rates of 105 kg N and 46 kg P ha−1. No-till increased soil water storage by 8–12% and improved WUE compared to conventional tillage, thus showing potentials for drought mitigation and economic use of fertilizers in drought-prone rainfed conditions in northern China. 相似文献
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J. Gominho A. LourençoP. Palma M.E. LourençoM.D. Curt J. FernándezH. Pereira 《Industrial Crops and Products》2011,33(1):1-6
Large scale cultivation of the cardoon Cynara cardunculus L. for biomass production was installed using common agricultural practices and machinery in a total of 77.4 ha in southern Portugal in a region characterized by very hot and dry summers. This species is a perennial with an annual growth cycle. Installation by sowing was successful in spite of the extreme drought that occurred during this first cycle (221 mm), and the plants developed well during the second cycle (with 556 mm rainfall) with a mean density of 27 thousand plants per ha. Aerial photographs showed that 45.8 ha of the field had over 50% of ground cover by cardoon plants. The observed differences in soil occupation could be explained by rock outcrops, soil heterogeneity and land topography. The field biomass yield was estimated at 7.5 t ha−1 and the plants at harvest had on average 2.1 m height and 2.2 cm stalk diameter, with 5.3 capitula per plant. Stalks represented 59.1% of total dry biomass. The capitula contain small oil seeds with an average of 126 seeds per capitulum and weighing 32 g per 1000 seeds. The mean seed yield was 603 kg ha−1. The results of this experiment confirm that Cynara crops are suitable for biomass production in Mediterranean regions and that large scale operation can be applied including whole plant harvest or field fractionation for seed recovery. Careful attention to cultural practices was deemed important for field homogeneity and production. The observed plant variation, namely in oil seed production, suggests potential improvements through breeding. 相似文献
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研究比较了垄上覆膜、行间覆膜、大垄直播、小垄直播4种栽培方式。结果表明:大垄行间覆膜比直播能显著提高玉米子粒重,提高产量,提高土壤温度,保持土壤湿度,生育期提前,减少土壤容重,增大土壤孔隙度,提高产量构成因素,使产量提高13.58%。 相似文献
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为探明不同幅宽条播和覆膜穴播对河套灌区有机春小麦的产量、开花期农艺性状、杂草发生程度及经济效益的影响,设置覆膜穴播（FM）、宽幅16 cm条播（KF16）、宽幅7 cm条播（KF7）、窄幅窄行11 cm条播（ZF11）、窄幅宽行15 cm条播（ZF15）共5种不同播种方式,研究了不同处理下有机小麦开花期农艺性状、籽粒产量、杂草密度及各生育时期杂草干物质量和经济效益的差异。结果表明,与ZF15处理相比,FM处理显著提高了有机小麦开花期株高、旗叶长、旗叶面积、单株叶面积、旗叶SPAD值,KF16处理明显改善了旗叶光合速率,而KF7和ZF11处理的叶面积指数显著低于其他处理;FM、KF16、ZF11、KF7处理的籽粒产量较ZF15处理分别提高了33.0%、27.2%、21.5%、14.9%;KF16和FM处理的杂草总密度和杂草干物质量较ZF15降低了 75.6%、92.8%和73.9%、81.4%,纯收益分别增加了7 680.4元·hm-2和7 246.7元·hm-2。经相关分析,杂草干物质量与有机小麦产量呈显著或极显著负相关。综上所述,宽幅16 cm条播和覆膜穴播可有效降低杂草密度及干物质量,促进小麦生长发育,提高有机小麦籽粒产量。 相似文献
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通过短季棉鲁棉532覆膜晚播和无膜晚播种植模式与春棉鲁棉258常规种植模式进行比较,探索适宜山东黄河三角洲地区气候地理条件的短季棉最佳种植模式,为大面积推广短季棉种植模式提供依据。结果表明,短季棉覆膜晚播种植模式对促进生长、增产、增效效果不突出;短季棉无膜晚播种植模式比其他模式可明显减少管理用工,降低植棉投入,比覆膜晚播效益略高,比春棉产量和效益均降低。建议采用短季棉无膜晚播与黑麦草(饲草)连作模式在黄河三角洲地区大面积推广,以提高短季棉的种植效益。 相似文献
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半干旱地区玉米覆膜方式研究 总被引：5，自引：1，他引：4
干旱是制约玉米生产的主要因子。试验研究7种不同覆膜方式的土壤含水量、土壤温度、玉米生育期、农艺性状及产量,探求不同覆膜方式对半干旱地区玉米产量的影响。结果表明,顶凌覆膜优于春覆膜,全地面覆膜优于半覆膜平铺,其中全膜顶凌双垄沟栽培模式产量达到12 691.9 kg/hm2,较普通种植模式增产46.10%,较裸地种植增产77.98%,是一项适合半干旱地区的玉米高产栽培技术。 相似文献