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1.
A field experiment was conducted on silty clay loam soil in the years 2011–2012. Two sesame (Sesamum indicum L.) cultivars (Local Black and Local White) were evaluated using various 3 different sowing dates (20th June, 10th and 30th July) and four agrotechnical level (0, 40, 80 and 120 kg N ha–1) at New Developmental Farm The University of Agriculture, Peshawar, Pakistan. The objective of this study was to evaluate the effects of sowing dates on growth, yield and oil fatty acid composition of two sesame cultivars grown under different nitrogen fertilization. Results showed that cv. Local Black was characterized by significantly higher content of oil (47%), seed yield (696 kg ha–1) and oil yield (335 kg ha–1) while cv. Local White had higher palmitic acid (8%) and linoleic acid (38.7%). Yield and its main components were positively affected by the earlier sowing date. With regard to fatty acid composition, a decrease in oleic and stearic acid and an increase in linoleic and palmitic acid were observed. At early sowing, oleic and palmitic acid decreased whereas linoleic and stearic acid increased. The decrease in the oleic/linoleic acid ratio observed at early sowing, suggests a possible role of temperature on the activity of oleate desaturase in the developing seeds. Intensive technology of cultivation (120 kg N ha–1), compared to the economical technology (40 kg N ha–1), significantly increased the seed yield of both sesame cultivars. This was due to higher number of branches, Capsules m–2, capsules plant–1, seeds capsule–1 and 1000 seed weight (g). The intensive technology of cultivation had a beneficial effect on the content of palmitic acid, linolenic acid and oleic acid in sesame seed.  相似文献   
2.
Shoot:root (S:R) response in four winter C3-grasses (cereals) viz. wheat (Triticum aestivum L.), rye (Secale cereale L.), barley (Hordeum vulgare L.) and oats (Avena sativa L.) was investigated under eight different NPK sources (S1 = 20-20-20, S2 = 20-27-5, S3 = 7-22-8, S4 = 10-10-10-20S, S5 = 11-15-11, S6 = 31-11-11, S7 = 24-8-16, and S8 = 19-6-12) in pot experiment at Dryland Agriculture Institute, West Texas A&M University, Canyon, Texas, USA during winter 2009–2010. The experiment was performed in completely randomized design (CRD) with three repeats. The objective of this experiment was to investigate whether the S:R of winter cereals differ or not when applied with different NPK sources. Considerable variations in the shoot: root was noticed in the four grasses at different growth stages, i.e., 30, 60 and 90 days after emergence (DAE) when applied with different NPK fertilizers sources. Wheat had the highest S:R of 3.4 at 30 days after emergence (DAE), barley at 60 DAE (6.5), while oats at 90 DAE (3.9). Among the NPK sources, crops had the highest S:R of 3.6, 6.2 and 3.7 when applied with S3, S2, and S6 at 30, 60 and 90 DAE, respectively. Shoot to root ratio showed positive relationship with increase in shoot weight and negative relationship with increase in root weight. The NPK fertilizer S6 (31: 11: 11), an acid loving fertilizer had negative effects on the shoot and root development of cool season cereals, but among these cereals under study, barley and oats roots were affected more than wheat and rye. It was concluded from this present study, that the four cool season cereals responded differently in terms of shoot: root to different NPK fertilizers at different growth stages.  相似文献   
3.
The use of appropriate source of phosphorus (P) fertilizer at different planting densities has considerable impact on growth, grain yield as well as profitability of maize (Zea mays L). Field experiment was conducted in order to investigate the impact of P sources [(S0 = P not applied, S1 = SSP (single super phosphate) S2 = NP (nitrophos), and S3 = DAP (diammonium phosphate)] on maize growth analysis, yield and economic returns planted at different planting densities (D1 = 40,000, D2 = 60,000, D3 = 80,000, and D4 = 100,000 plants ha?1) at the New Developmental Agricultural Research Farm of Khyber Pakhtunkhwa Agricultural University, Peshawar, Pakistan, during summer 2006. This paper reports the profitability data with two objectives: 1) to compare agronomic efficiency and profitability of P-fertilizers, and 2) to know whether plant densities affect agronomic efficiency and profitability of P-fertilizers. Application of DAP and SSP resulted in higher partial factor productivity (PFP) (63.58 and 61.92 kg grains kg?1 P), agronomic efficiency (AE) (13.01 and 13.71 kg grains kg?1 P) and net returns (NR) (Rs. 16,289 and 16,204 ha?1), respectively, while NP stood at the bottom in the ranking with lower PFP (57.16 kg grains kg?1 P), AE (8.94 kg grains kg?1 P) and NR (Rs. 4,472 ha?1). Among the plant densities, D3 stood first with maximum PFP (69.60 kg grains kg?1 P), AE (18.21 kg grains kg?1 P) and NR (Rs. 21,461 ha?1) as compared to other plant densities. In conclusion, the findings suggest that growing maize at D3 applied with either SSP or DAP is more profitable in the wheat-maize cropping system in the study area.  相似文献   
4.
Shoot-root ratio (S:R), dry matter partitioning (DMP), and water use efficiency (WUE) response of wheat (Triticum aestivum L.) vs. rye (Secale cereale L.) was investigated under organic [organic compost (OC), Miracle Grow (MG), sunshine peat moss (SPM), and Garden Basic peat humus (GBPM)], and inorganic soils [canyon soil (CS) and amarillo soil (AS)] in pot experiment at Dryland Agriculture Institute, West Texas A&M University, College Station, Texas, USA, during winter 2009–2010. The experiment was performed in completely randomized design (CRD) with three repeats. The objective of this experiment was whether S:R, DMP, and WUE of wheat versus rye differ under organic and inorganic soils. The results revealed that both crops responded differently in terms of S:R, DMP, and WUE under different organic and inorganic soils. Wheat had higher WUE than rye at different growth stages. Among the soil types, the three organic soils (MG, SPM, and GBPS) had higher WUE than the two inorganic (CS and AS) soils. The higher WUE of both crops when grown in organic soils such as MG, SPM, and GBPS was due to the higher dry matter partitioning to shoots and roots. The total dry weight plant?1 showed positive relationship with WUE.  相似文献   
5.
Tropical Animal Health and Production - Poor quality feed and lack of feed resource conservation in Pakistan are the major constraints influencing livestock production systems in the country. In...  相似文献   
6.
The objectives of this study were to investigate the effects of dietary n‐6/n‐3 fatty acid (FA) ratio on digestibility, blood metabolites and FA profile of Hanwoo heifers. Fifteen Hanwoo heifers (22 ± 3 months old; 357 ± 69.7 kg) were randomly assigned to three dietary treatments with n‐6/n‐3 FA ratios of 2.07, 5.18 and 7.37. The animals were housed individually in digestion crates and fed total mixed rations at 2.2% of body weight for 2 weeks of adaptation and 1 week of collection. Treatment effects on in vivo digestibility, plasma metabolite and fatty acid profiles, and in vitro ruminal fermentation and fatty acid profiles were examined. In vivo digestibility was not affected (P > 0.05) by dietary n‐6/n‐3 FA ratio. However, in vitro dry matter digestibility and concentrations of total volatile fatty acids and propionate decreased (P < 0.05) linearly with increasing n‐6/n‐3 FA ratio. Plasma insulin and progesterone increased linearly (P < 0.05), but linolenic acid and total n‐3 FA decreased linearly (P < 0.05) with increasing n‐6/n‐3 ratio. Increasing the dietary n‐6/n‐3 FA ratio can increase the n‐6/n‐3 FA ratio in plasma and ruminal fluid as well as plasma progesterone secretion.  相似文献   
7.
This study estimated the effects of hybrid and bacterial inoculant on fermentation quality and fatty acid profile of barley silages. Yuyeon (Silkless) and Youngyang (Silking) barley hybrids were harvested at 24.9 and 27.1% dry matter, respectively, and chopped to 10 cm lengths. Each hybrid was treated with or without an inoculant (2 × 104 colony‐forming units/g of Lactobacillus plantarum). A total of 48 silos were prepared in an experiment with a 2 × 2 (hybrid × inoculant) treatment arrangement with four replications and three ensiling durations (2, 7 and 100 days). After 100 days of ensiling, Yuyeon silage had higher (P < 0.05) in vitro dry matter digestibility and C18:3n‐3 than Youngyang silage. Youngyang silage had higher (P < 0.05) acetic acid and C18:2n‐6 than Yuyeon silage. Inoculation reduced the C18:3n‐3 concentration of both hybrids and increased (P < 0.05) the C18:2n‐6 of Youngyang. However, fermentation quality was not improved by the inoculant. These results indicate that Yuyeon hybrid might have better potential benefits on animal performances due to its smooth awn and silkless nature, and higher in vitro dry matter digestibility. Its higher C18:3n‐3 would be better for improving fatty acid profile of meat or milk than Youngyang hybrid.  相似文献   
8.
Imran  Amanullah 《Gesunde Pflanzen》2022,74(1):167-176

Effective weed management in maize-wheat (M-W) cropping systems are accountable for higher yield and plant biomass. The objective of this study was to evaluate the effectiveness of manual weeding and chemicals (pre- and post-emergence herbicide) for actual weed control to enhance maize yield and M?W system productivity. Herbicides were treated as pre-emergence (sole), post-emergence (sole) and its combined application (pre- and post-emergence) for weed eradication and suppression. Sole pre-emergence herbicide (acetyclour?+?atrazine) and sole post-emergence herbicides (nicosulfuron), and its mixed application were used in the experiments. The experiment was comprised on 6 treatments with one weedy check or control plot: W1?=?weedy check, W2?=?acetyclour?+?atrazine, W3?=?atrazine, W4?=?nicosulfuron, W5?=?nicosulfuron?+?atrazine, W6?=?acetyclour?+?atrazine?+?nicosulfuron and W7?=?manual weeding. Main weeds were Cyperus rotundus, Tribulus terrestris, Dactyloctenium aegyptium and Cynodon dactylon. Experiential findings revealed that manual weeding was found most effective in terms of controlling weed and suppression. Among the herbicides application, promising results in terms of weed destruction and suppression were shown by combined application of acetyclour?+?atrazine?+?nicosulfuron which effectively controlled weeds as compared to other treatments. It was concluded that manual weeding drastically reduced weeds frequency and biomass while among the herbicides application acetyclour?+?atrazine and nicosulfuron could be promising for weeds suppression and clamp downing as compared to all other treatments under M?W cropping system.

  相似文献   
9.
ABSTRACT

Nitrogen (N) and plant density are considered some of the most important factors affecting crop phenology (days to tasseling, silking, and maturity), morphology (leaves plant?1, seeds ear?1, ears 100 plants?1) and grain yield. The effects of plant density and N on phenology, morphology, and yield of maize (Zea mays L.) at Peshawar in northwestern Pakistan were evaluated during 2002 to 2004. The 2 × 3 × 6 factorial experiment was designed having two plant densities (60,000 and 100,000 plants ha?1) and three N levels (60, 120, and 180 kg N ha?1) applied to main plots, while six split application of N in different proportions were applied to subplots in two equal, three equal, three unequal, four equal, five equal and five unequal splits at sowing and with 1st, 2nd, 3rd, and 4th irrigation at two week intervals. All the phenological characteristics were significantly affected by year, plant density, rate and timing of nitrogen application. Year and plant density had no significant effect while rates and split application of N had significant effects on the leaf number plant?1 and seed number ear?1. Year, plant density and N rate had significant effects while N splits had no significant effects on the number of ears 100 plants?1 of maize. Significantly higher grain yield was observed under high plant densities, high N rate and split application of N, while its response to year effects was statistically non-significant. Tasseling, silking and physiological maturity were delayed and maximum grain yield was obtained from those plots maintained at higher plant density. Delaying in the phenological characteristics while increasing the number of leaves and seeds plant?1, and number of ears 100 plant?1 through high rate and split application of N results in maximum yield of maize at Peshawar. This study suggested that maize production can be maximized through high plant density and high N split application.  相似文献   
10.
Improper sulfur (S) and potassium (K) fertilizer management, particularly with continued soil nutrient mining, is one of the major factors contributing to low seed yield of canola in northwestern Pakistan. A field experiment was conducted in 2007?2008 on a S and K deficient clay loam soil at the Research Farm of NWFP (Northwest Frontier Province) Agricultural University, Peshawar, Pakistan, with an objective to determine seed yield and yield components response of Brassica oilseed rape versus mustard to S and K application. Twenty treatments in a randomized complete block design were consisted of two oilseed rape (B. napus canola) and mustard (B. juncea canola) genotypes at three rates each of S (15, 30, and 45 kg S ha?1) and K (30, 60, and 90 kg K ha?1) fertilizers plus one control (no S and K applied). Seed yield and yield components increased significantly with K and S fertilization as compared to the zero-S/zero-K control. Both genotypes responded positively for seed yield and yield components to K and S fertilization, but the magnitude of response varied with levels of S and K, as well as combined K + S applications. It is concluded that a combination of 60 kg K + 30 kg S ha?1 would improve seed yield and yield components of rape and mustard in the study area and contribute significantly to increased production. Growing B. napus was better than B. juncea in the study area, because B. napus produced significantly higher seed yield and yield components than B. juncea, indicating that yield components are the most important criteria for selection of Brassica genotypes for higher seed yield.  相似文献   
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