PDF(Pubmed)
Abstract：
Effective management of fertilizers is essential in influencing the prevalence of insects in rice (Oryza sativa L.) fields. Over two years (2019-20 and 2020-21), an experiment conducted at Bangladesh Rice Research Institute (BRRI), Habiganj, during the boro season aimed to identify the most effective multidimensional treatment (EMT) by testing various combinations of chemical fertilizers and its effect on rice insects. The goal was to optimize rice grain yield while minimizing harmful insect infestation and supporting natural enemies. Eight different chemical fertilizer applications were used as follows: T1 contained a full mix of nitrogen (N), phosphorus (P), potassium (K), and sulfur (S); T2 had PKS but lacked N; T3 had NKS but lacked P; T4 had NPS but lacked K; T5 had NPK but lacked S; T6 had KS but lacked N and P; T7 had PS but lacked N and K; and T8 lacked all four elements - N, P, K, and S. The relationship between the dynamics of harmful insects and natural enemies was highly positively correlated (r = 0.72 to 0.97). In two consecutive growing years, the 2020-21 season exhibited notably higher counts of harmful insects, with Rice Leafroller (RLR) dominating in the booting stage and White Backed Planthopper (WBPH) in mid-tillering, while Green Mirid Bug (GMB) prevailed among natural enemies across both stages, surpassing insect pest counts, notably GMB, Lady bird beetle (LBB), Carabid beetle (CDB), and Staphylinid (STD). However, the yield was notably higher in the 2019-20 growing season despite these pest pressures. Throughout the mid-tillering and booting stages, T1 consistently exhibited the highest average populations of harmful insects and natural enemies, while T7 demonstrated the lowest count of harmful insects, followed by T2 at both growth stages. Additionally, the highest grain yield (GY) was consistently recorded in T1, followed by T5, T6, and T3, with yields of 7.98 t/ha, 7.63 t/ha, 7.38 t/ha, and 7.33 t/ha, respectively. In both stages, beneficial insects prevailed over harmful ones in all fertilizer applications, with significant declines noted in T2 and T7. Factor analysis showed successful selection for EMT in the MGIDI index for all variables except INT and GY during the 2019-20 season, with selection differentials (SD) ranging from -0.10 to 8.29. However, in 2020-21, selection was achieved for all variables with SD ranging from 0.37 to 6.08. According to the MGIDI index, the top-ranked EMTs were identified as T4 and T3 for the 2019-20 period, and T3 and T5 for the 2020-21 period. The EMT shared in both years, T3, proved effective because of its positive impact on enhancing natural enemies throughout both periods (with SD ranging from 4.76 to 8.29 for 2019-20 and 3.03 to 6.08 for 2020-21), and its notable contribution to rice grain yield (SD = 0.37) in 2020-21. This study uniquely integrates EMT to optimize rice grain yield while simultaneously managing harmful insect infestations and supporting natural enemies, addressing a critical need in sustainable rice cultivation. The suggestion is to give preference to fertilizer application T3, which omits P but contains N and K, to improve rice grain yield and boost natural enemies, thereby reducing harmful insect infestation. Moreover, future investigations should concentrate on refining fertilizer blends to strike a harmony between maximizing yield and fostering ecological robustness in rice cultivation.
摘要：
肥料的有效管理对于影响水稻（OryzasativaL.）田间昆虫的流行至关重要。超过两年（2019-20年和2020-21年），在孟加拉国水稻研究所（BRRI）进行的一项实验，Habiganj,在boro季节，旨在通过测试化学肥料的各种组合及其对水稻昆虫的影响来确定最有效的多维处理（EMT）。目标是优化水稻产量，同时最大程度地减少有害昆虫的侵扰并支持天敌。八种不同的化肥使用如下：T1含有氮（N）的充分混合物，磷（P），钾（K），和硫（S）；T2具有PKS，但缺少N；T3具有NKS，但缺少P；T4具有NPS，但缺少K；T5具有NPK，但缺少S；T6具有KS，但缺少N和P；T7具有PS，但缺少N和K；T8缺少所有四种元素-N，P,K,和S。有害昆虫的动态与天敌之间呈高度正相关（r=0.72至0.97）。在连续两年的成长中，2020-21赛季表现出明显更高的有害昆虫数量，水稻卷叶机（RLR）在孕穗期占主导地位，而白背飞虱（WBPH）在分till期占主导地位，当绿色MiridBug（GMB）在两个阶段的天敌中盛行时，超过害虫数量，特别是GMB,夫人鸟甲虫（LBB），甲虫(CDB),和葡萄球菌（STD）。然而,尽管有这些虫害压力，但2019-20年的生长季节产量明显更高。在整个中耕和引导阶段，T1始终表现出最高的有害昆虫和天敌的平均种群，虽然T7显示了最低数量的有害昆虫，其次是T2在两个生长阶段。此外,最高的粮食产量（GY）始终记录在T1，其次是T5，T6和T3，单产为7.98t/ha，7.63吨/公顷，7.38吨/公顷，和7.33吨/公顷，分别。在这两个阶段,在所有肥料施用中，有益昆虫胜过有害昆虫，T2和T7显著下降。因素分析显示，在2019-20赛季中，除了INT和GY之外，所有变量的MGIDI指数中EMT都被成功选择，选择差异（SD）范围为-0.10至8.29。然而,在2020-21年，所有变量均实现了选择，SD范围为0.37至6.08。根据MGIDI指数，在2019-20年期间，排名最高的EMT被确定为T4和T3，以及2020-21年期间的T3和T5。EMT在这两年分享了，T3，被证明是有效的，因为它在两个时期都对增强天敌具有积极影响（2019-20年的SD范围为4.76至8.29，2020-21年的SD范围为3.03至6.08），2020-21年对水稻籽粒产量的贡献显著(SD=0.37)。这项研究独特地整合了EMT，以优化水稻籽粒产量，同时管理有害昆虫的侵扰和支持天敌，解决可持续水稻种植的关键需求。建议优先使用T3的肥料，该肥料省略了P，但包含N和K，为了提高水稻产量和增强天敌，从而减少有害昆虫的侵扰。此外，未来的研究应集中在精炼肥料混合物上，以在水稻种植中实现产量最大化和生态稳健性之间的和谐。
