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Zainal Abidin Cik Mohd Rizuan Mohd Noor Hafidzi Hamid Noor Hisham Ravindran Shakinah Puan Chong Leong Kasim Azhar Salim Hasber 《Journal of pest science》2022,95(2):1009-1022
Journal of Pest Science - In Peninsular Malaysia, barn owls (Tyto javanica javanica) have been utilized as biological control of rats since the 1960s. In this study, the impact of introduced barn... 相似文献
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夏玉米的干旱适应性及其生理机制的研究 总被引：25，自引：1，他引：25
1987～1988年,分别在大田和遮雨塑料棚条件下,测定并分析了三个抗性不同的夏玉米杂交种与干旱适应性有关的一些生理特性.结果表明,夏玉米杂交种受旱后,对干旱均表现出了程度不同的适应性;高抗杂交种以较强的根系活力、气孔调节能力和广泛的水分适应性体现其抗旱性,在耐旱性上则主要表现为受害后叶绿素含量较稳定,膜损伤小,游离脯氨酸积累量大.二者综合作用的结果、使其抗旱系数大,经济产量高.此外,还对夏玉米抗旱机理以及气孔扩散阻力、游离脯氨酸积累与抗旱性的关系进行了初步探讨. 相似文献
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Ground cover is an essential element in the selection of habitats by small mammals. It provides shelter, foraging opportunities and a hiding place from predators. In oil palm plantations rodents are abundant yet the relationships between ground cover structure and rats are not well understood. Plantation management emphasizes maximisation of oil palm yield by reducing rat damage and competition from weeds, typically through chemical control. This study examined the relationships between ground cover, including undergrowth and frond piles, and rat abundance. Rat trapping and vegetation assessment were conducted simultaneously in five study plots in the Labu Estate, Negeri Sembilan, Malaysia. Over 21,000 trap-nights 1190 individual rats were captured and these data were analysed using spatial analysis by distance indices (SADIE). No significant clustering of rats was observed within any plot over time. Redundancy analyses suggested that the overall occurrence of rats, especially Rattus argentiventer, was positively correlated with vegetation cover and height. This implies that habitat complexity is important to rats, even in a relatively simple agroecosystem. Results of the SADIE analyses were inconsistent, perhaps due to highly variable management practices in the plantations. The findings from this study suggest that using an integrated approach in the control of both weeds and rats in oil palm plantations may maximise the benefits from weeding while reducing the production loss due to rats and the need for chemical control of rats. 相似文献
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Twelve, 400‐m2 earthen ponds at Walailak University, Thailand, were used to investigate the effects of fertilizer application rates on water quality, bottom soil, and production of giant gourami, Osphronemus goramy. Fertilizer rates of 0, 6, 9, and 12 kg N plus 0, 3, 4.5, and 6 kg P2O5 /ha (N:P2O5 = 2:1) applied at 3‐wk intervals were replicated three times in a completely randomized design. Ammonium phosphate and ammonium sulfate were sources of nitrogen and phosphorus. Fish averaged 8.8 g and were stocked at 1 fish/m2. The highest final weight, growth rate, and net production of giant gourami were achieved with 9 kg N plus 4.5 kg P2O5/ha. Chlorophyll a concentration was correlated with total nitrogen concentration (R2 = 0.574; P < 0.05) and total phosphorus concentration (R2 = 0.600, P < 0.05). Fish production and chlorophyll a concentration were also correlated (0.826; P < 0.05). Chlorophyll a concentration and fish production declined at total hardness concentrations above about 50 mg/L – likely from precipitation of fertilizer phosphorus as calcium phosphate. Pond bottom soil properties did not change in relationship to fertilizer rate. 相似文献
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Claude E. Boyd Ken Corpron Eric Bernard Puan Pengsang 《Journal of the World Aquaculture Society》2006,37(1):41-47
A phosphorus budget for a single crop was prepared for a 685‐ha semi‐intensive shrimp farm that consistently has produced about 3000 tonnes/yr of black tiger prawn, Penaeus monodon. Phosphorus inputs were shrimp stock, 0.31 kg/ha; triple superphosphate, 1.38 kg/ha; incoming water, 25.8 kg/ha; and feed, 65.3 kg/ha. Phosphorus outputs were harvested shrimp, 5.43 kg/ha, and outflow for water exchange and draining, 42.7 kg/ha. The high clay‐content soil in pond bottoms adsorbed 45.2 kg/ha of phosphorus. Water was taken from and released back into the same estuary and bay. The phosphorus contribution of shrimp farming to the receiving water body was the difference between the amount of phosphorus in effluent and that in the incoming water, which was 16.9 kg/ha. Bottom soil accumulated 67.8% of phosphorus added to the ponds. Another estimate of soil phosphorus uptake based on the relationship between cumulative phosphorus applied to ponds as fertilizer and feed and soil phosphorus concentration suggested that 63.2% of fertilizer and feed phosphorus had accumulated in pond bottoms. The farm effluent phosphorus load was 23.5 tonnes/yr. The estuary and bay system has an estimated volume of 4.8 × 109 m3, and the annual phosphorus input from the farm had a concentration equivalent of 0.005 mg/L, and there were no other major inputs of phosphorus. The estuary and bay are flushed by freshwater inflow and tidal action, and the farm input is not likely to cause eutrophication. 相似文献
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日龄与体重相近的长白×赣州白杂交肉猪１６头，随机分为两组：Ⅰ（对照组），Ⅱ（试验组），公母各半。猪体重接近４５ｋｇ时，Ⅱ组猪饲料添加０．８ｍｇ／Ｌβ－肾上腺素能受体激动剂Ｃｌｅｎｂｕｔｅｒｏｌ（ＣＬ），直到屠宰前８ｄ停止添加。在猪接近８５ｋｇ体重时，两组猪同时屠宰测定。结果表明，ＣＬ使猪的生长速度提高９．６％，平均日增重提高２０％，饲料转化率提高１７．４５％，眼肌面积增加１５．１％，瘦肉率增加１８．３％，背膘厚度减少１５．３％，脂肪率减少２３．２％（均Ｐ＜０．０５）。胴体在水中的比重（胴体在水中重／胴体重），试验猪比对照猪增加５０％以上（Ｐ＜０．０１），说明饲料中添加ＣＬ使猪胴体的瘦肉成分增多，脂肪成分减少。 相似文献
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