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21.
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   
22.
The objective of this study was to examine the relationship between heterosis and genetic distance in upland cotton (Gossypium hirsutum L.). Heterosis in the different environments was evaluated and the relationship between heterosis and genetic distance (GD) was determined based on SSR markers for yield quantitative trait loci (QTL). Yields of seed cotton and lint showed a linear relationship with mid‐parent heterosis (MPH) and better‐parent heterosis (BPH). The variation in heterosis for other traits and their correlation with GD may be due to environmental factors or the effort of QTLs tested in the present study may vary in different environments. The present findings provide a foundation for heterotic grouping of parental lines and breeding of new cotton hybrids with improved seed cotton yield. This study calls for more research with stable QTLs as well as advance molecular marker techniques may be used in predicting yield heterosis in a more precise and reliable manner.  相似文献   
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Soil salinity is one of the major production constraints. Development and planting of salt‐tolerant varieties can reduce yield losses due to salinity. We screened 185 rice genotypes at germination stage in petri dishes under control, 50, 100 and 150 mm salt stress, and at seedling stage in Yoshida's hydroponic nutrient solution under control, 50 and 100 mm salt stress. At germination stage, 15 genotypes including Nona Bokra, Sonahri Kangni, 7421, 7423 and 7467, whereas at seedling stage, 28 genotypes including Nona Bokra, Jajai‐77, KSK‐133, KSK‐282, Fakhr‐e‐Malakand, Pakhal, IR‐6, Khushboo‐95, Shahkar and Shua‐92 were found salt tolerant. Basmati‐370, Mushkan, Homo‐46 and accessions 7436, 7437 and 7720 were sensitive to salinity at both germination and seedling stage. We further screened a subset of 33 salt‐tolerant and salt‐sensitive genotypes with SSR markers. Four SSR markers (RM19, RM171, RM172 and RM189) showed significant association with two or more of the studied traits under 50, 100 and 150 mm salt stress. These markers may be further tested for their potential in marker‐assisted selection. The salt‐tolerant genotypes identified in this study may prove useful in the development of salt‐tolerant rice varieties in adapted genetic background.  相似文献   
25.
为了找到安全有效的防控香蕉枯萎病的生防菌株,采用组织分离法从香蕉叶片中分离出内生细菌菌株YX-11.采用形态学、生物化学和16 S rDNA基因序列分析,该菌株被鉴定为贝莱斯芽孢杆菌Bacillus velezensis.YX-11具有溶磷、解钾和固氮的能力,还可以促进香蕉的生长,能抑制10种植物病原菌,其中对香蕉枯萎病菌、烟草疫霉病菌和烟草赤星病菌的抑制率分别达71.30%、72.77%和72.19%.它的带菌苗结合生物有机肥施用,以及多次喷施对田间香蕉枯萎病的防治效果达75.56%.  相似文献   
26.
The study investigated the performance response of different dietary protein and energy levels of Nili-Ravi buffalo calves. Sixty buffalo calves of 12–15 months of age and similar body weight (140 ± 14 kg) were divided in to 12 groups, five animals in each group, according to 4 × 3 factorial arrangements. Twelve rations were formulated containing four levels of crude protein (CP; 10.5%, 12.20%, 13.80%, and 15.55%) each with three levels (1.72, 2.11, and 2.5 Mcal/Kg) of metabolizable energy (ME). Experiment lasted for 100 days; first 10 days were given for dietary adaptation. Daily feed consumption in calves fed all experimental diets were statistically significant (p < 0.05) across all treatments. Higher feed intake was observed in buffalo calves fed diets containing 12.20% and 13.85% CP with 2.11 Mcal/kg ME. Results of dry matter (DM) digestion were significantly different (p < 0.05) across all treatments. There was a quadratic (p < 0.05) response of DM digestibility for levels of dietary protein while, curvilinear (p < 0.05) trend with respect to dietary energy levels. Daily weight gain of buffalo calves did not show any treatment effect. The outcome of the present study indicate that 12–15-month-old buffalo calves perform adequately well when fed on diets containing 12.2% CP and 2.10 ME Mcal/Kg.  相似文献   
27.
To investigate the impact of CaCl2 concentrations and storage duration on quality of peach (Prunus persica), a research was conducted at postharvest Laboratory, Department of Horticulture, The University of Agriculture, Peshawar, Pakistan during 2012–2013. The experiment was laid out in Completely Randomized Design (CRD) with factorial arrangement repeated three times. The peach fruits (cv. Texas A 69) were harvested at physiological maturity stage from peach orchard, Horticulture Farm. The fruits were dipped in 0, 2 and 4% CaCl2 solution for 10 min and transferred to cold storage having ±8–10°C with relative humidity of 80–85%. The application of CaCl2 solution and storage duration significantly influenced the fruit quality of peach fruit. However, the application of CaCl2 solution significantly reduced weight loss (4.98%), disease incidence (2.08%), total sugars (5.31%), TSS-Acid ratio (16.27), TSS(7.380Brix) and increased the fruit firmness (2.21 kg cm–2) titratable acidity (0.47%) and Ascorbic acid (5.35 mg/100 g) of peach fruits. The storage duration of peach fruit also significantly affected the fruit quality attributes during storage. The peach fruit stored for 30 days showed less fruit firmness (0.74 kg cm–2) and titratable acidity (0.31%), Ascorbic acid (4.45 mg/100 g) and increased weight loss (19.74%), disease incidence (16.11%), total sugars (6.07%), TSSAcid ratio (27.62) and TSS(8.540Brix) of peach fruit. Based on the findings of this study, it is concluded that the peach fruit should be treated with 4% CaCl2 solution to retain the quality attributes for 30 days storage.  相似文献   
28.
Precision Agriculture - Controlling weed infestation through chemicals (herbicides &amp; pesticides) is essential for crop yield. However, excessive use of these chemicals has caused severe...  相似文献   
29.
In present study, a total of 275 retail cereal samples including rice, corn and corn products was analyzed for the presence of aflatoxins and ochratoxin A (OTA) using HPLC equipped with a fluorescence detector. The data has shown that 38 out of 68 samples of rice, 37/105 of corn and 43/102 samples of corn products have been found contaminated with AFs, average level of AFB1 and total AFs, 8.23 and 19.54, 7.90 and 12.08, and 5.47 and 7.85 μg/kg, respectively. Furthermore, 34, 28 and 26 numbers of rice, corn and corn product samples were found to be contaminated with OTA with an average level of 12.94, 5.29 and 3.69 μg/kg, respectively. The samples of rice, corn and corn products found above the permissible European Union (EU) limit for AFB1 and total AFs were 18, 13 and 14 and 28, 14 and 20%, respectively; however, the samples of rice, corn and corn products above the EU limit were 40, 14 and 15%, respectively.  相似文献   
30.
The prevalence of Streptococcus equi serovar equi (S.equi) in nasal discharge and pus samples from sub‐mandibular lymph nodes in mules at the Remount Depot, Sargodha was examined and total serum proteins, serum albumin, serum globulin and fibrinogen measured. A total of 250 nasal swabs and pus samples were collected from mules and examined microbiologically: 99 (39.6%) were positive for S. equi. A higher occurrence of S. equi was recorded in foals as compared to adults. The concentrations of total serum protein, serum globulin and fibrinogen were significantly increased (P<0.05), while the concentration of serum albumin significantly decreased (P<0.05) in strangles‐affected mules. It was concluded that increased total serum proteins, serum globulin and fibrinogen along with decreased serum albumin were important indicators of infection by S. equi in mules.  相似文献   
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