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Removal of early fruiting branches with greater potassium doses caused more source and no sink at early stages of growth, leading to improved yield, yield components, and fiber quality traits in Bt cotton. The study used manual alteration of plant architecture (F1, no branch removal; F2, removal of first fruiting branch; F3, removal of first and second fruiting branches; F4, removal of all squares from first fruiting branch; F5, removal of all squares from first and second fruiting branches) and potassium rates (50, 100, and 150 kg ha?1) in a randomized complete block design and was repeated for 2 years (2011 and 2012). Increasing potassium application increased total bolls per plant and cotton yield to the greatest levels in F3 and F5, against lowest level in the control. Ginning out turn, fiber length, seed oil, and seed protein content were influenced by fruiting branch or square removal but the difference was less. Increasing potassium improved seed and fiber quality.  相似文献   
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Cold arid trans-Himalayan Ladakh region of India bordering with Pakistan and China is one of most elevated inhabited regions of the world. This region is highly vulnerable to climate change and serious environmental threats resulting in reduction in crop productivity due to risk of agricultural pest and plant pathogens. The present work describes the various diseases attacking barley from this region where the status of barley diseases has not yet been explored. Extensive field surveys were conducted for the first time during 2004-2005 and 475 fields were inspected at the 95 locations. Yellow rust, powdery mildew, leaf spot blotch/blight, covered smut, loose smut, foot/root rot and cereal cyst nematode causing molya disease were encountered during the survey. However, yellow rust, molya and foot/root rot were found as the most destructive diseases. Excellent hotspots of the encountered diseases were identified and marked which may be used for the screening of barley genotypes and determining the impact of climate change on plant diseases.  相似文献   
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Peach fruit is enriched with natural antioxidants but oxidation caused by biotic and abiotic stresses, reduce these antioxidants and consequently effect the quality and yield of the fruit. Therefore, an experiment was conducted to investigate the role of ascorbic acid to sustain the natural antioxidant activity, improve the fruit quality and yield of peach cultivars (Early Grand and Florida King). The peach cultivars, Early Grand and Florida King were tested against four levels of ascorbic acid (200, 400, 600 and 800?ppm) and compared with control as water spray. The foliar application of ascorbic acid significantly influenced anti-oxidant activity and physico-chemical attributes of peach cultivars. However, the foliar application of ascorbic acid @ 800?ppm significantly increased the fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity, antioxidant activity of fruit peel, with least percent infected fruits and fruit juice pH as compared to the rest of the treatments. Similarly, significant variation was recorded for peach cultivars regarding anti-oxidant activity and various physico-chemical attributes. The maximum fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity and TSS/TA ratio were noted in fruit of cultivar Florida King. On other side the foliar treated fruit of peach cultivar Early Grand had the highest percent infected fruits, fruit juice pH and antioxidant activity of fruit peel. It is concluded from the significant findings of present research that the peach cultivar Florida King performed better in terms of maximum fruit yield, whereas the cultivar Early Grand produced better quality fruits with high anti-oxidant activity when treated with 800?ppm of ascorbic acid as foliar spray.  相似文献   
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Commercial cultivation of Bt cotton produced higher boll load which led to stiff inter-original competition for photosynthates, resulting in early cessation of growth (premature senescence) due to more availability of sink and less sources. To overcome this problem, field experiment was conducted during 2011 and 2012 using five treatments of plant growth manipulation viz. no fruiting branch removal (F1), removal of first fruiting branch (F2), removal of first and second fruiting branch (F3), removal of all squares from first fruiting branch (F4), removal of all squares from first and second fruiting branches (F5), and three potassium (K) application rates viz. 50 kg ha?1 (K1), 100 kg ha?1 (K2), and 150 kg ha?1 (K3). More nodes above white flower were recorded in F5, followed by F3, while minimum were recorded in F1. Among potassium levels, maximum nodes above white flower were recorded in K3 followed by K2 and K1 during both years of study. Plant height recorded at physiological cutout stage or at maturity stage showed that plants gained more height with removal of all squares from first tosecond fruiting branches with higher potassium dose. Leaf K increased with increasing applied potassium and also with square/branch removal. So early removal of squares/fruiting branches along with higher potassium dose helped in delaying canopy senescence in Bt cotton.  相似文献   
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Effects of fodder availability and prolificacy on birth weight, weaning weight, weight at 6 and 9 months age, and pre- and post-weaning growth rates of Dera Din Panah goat were determined. A total of 350 records of Dera Din Panah (DDP) goats maintained at Sheep and Goat Development Centre, Rakh Khairewala, District Layyah, Punjab, Pakistan were analyzed using Harvey’s Mixed Model Least Squares and Maximum Likelihood computer program. Fodder availability significantly affected (P < 0.05) the birth weight, weaning weight, and pre-weaning daily gain. The effect of prolificacy on the birth weight, weaning weight, pre-weaning growth rate was significant (P < 0.05). Effects of fodder availability and prolificacy on average daily weight gain during different stages, such as from birth to 3 months of age (GR1), 3 to 6 months of age (GR2), 6 to 9 months of age (GR3), 9 to 12 months of age (GR4), and overall growth rate from birth to 12 months of age (GR5) age were determined.  相似文献   
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Sternbergia candida is an important endemic bulbous plant with beautiful white flowers. It grows on the rock slopes of Baba mountains under Lebanon Cedars in the Mugla province of Turkey with Mediterranean climate. The plant is vulnerable and endangered due to illegal collection for local and foreign flower industry. Fast developing tourism industry and rapid urbanization has also shown negative implications on its population. The study reports three years successful adaptation results of S. candida in the continental climate of Ankara in the Central Anatolia. Four groups of bulbs based on diameter (>2.45, 2.15–2.44, 1.85–2.14 and <1.84 cm) were collected from its natural habitat during March, April and May 1998 and were evaluated for frequency (%) of emergence, mean number of leaves per plant, mean plant height, frequency (%) of flowering, frequency (%) of fruit setting. mean number of bulbs per plant, and mean diameter (cm) of regenerated bulbs. All categories of bulbs could be multiplied and adapted successfully with variable frequency of fruit setting. However, the highest fruit set was recorded from 2.15–2.44 cm April collected bulbs. This indicated that the bulb diameter and collection time had clear implications on multiplication, propagation and adaptation of the plant.  相似文献   
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The aim of this study was to investigate the effect of various calcium:total phosphorus (Ca:tP) ratios due to addition of microbial phytase and 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] on the absorption levels of minerals. In a 42-day experiment repeated three times, 144 day-old male broiler chicks (ISA 220) were divided into six groups of eight chicks each. Diets containing two different (1:1 and 2:1) Ca levels were prepared. Groups 1, 2 and 3 received a diet of 1:1 Ca:tP ratio while Groups 4, 5 and 6 a diet of 1:2 Ca:tP ratio. These diets contained 1,25-(OH)2D3 and phytase in levels of 5 micrograms/kg and 600 FYT/kg, respectively. The faeces was collected to analyse the absorption of minerals. At the end of the study, the absorption levels of Ca, P, Zn, Mn and Cu were increased by the addition of phytase enzyme (p < 0.05). This effect was obvious in the 3rd week. On the other hand, in the 6th week only Ca and P absorption levels were influenced positively by the addition of phytase enzyme. The results proved the positive effect of phytase, an enzyme which is used for increasing the utilisation rate of phytate P, Ca and other minerals in broilers.  相似文献   
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