Vyavhare Suhas S, Way Michael O, Pearson Rebecca A, Medina Raul F
Texas A&M Agrilife Research and Extension Center, 1509 Aggie Dr., Beaumont TX 77713.
Department of Entomology, Texas A&M University, 2475 TAMU College Station, TX 77843.
J Econ Entomol. 2015 Aug;108(4):1516-25. doi: 10.1093/jee/tov132. Epub 2015 May 26.
Studies done in Brazilian soybean, Glycine max (L.) Merril, in the 1970s suggested the redbanded stink bug, Piezodorus guildinii (Westwood), is principally responsible for delayed maturity in this crop. This stink bug species has recently emerged as a serious pest of soybean in the southern United States, where little is known about its association with the occurrence of delayed maturity disorder. Also, the mechanism behind stink bug-induced soybean delayed maturity remains unknown. It is believed that stink bug feeding during pod development stages results in reduced pod-seed load, causing alteration of source-sink ratio and eventually delayed maturity. To determine the P. guildinii threshold triggering delayed maturity in soybean, experiments were conducted with varying levels of P. guildinii infestation (0, 2, 4, and 8 adults per 0.3 m) during the R4 to R5 soybean growth stages. In addition, to determine if soybean delayed maturity is exclusively because of reduced pod load, experiments with different levels of mechanical pod removal (0, 25, 50, and 75%) were conducted on field-grown soybeans. P. guildinii densities up to 4 adults per 0.3 m did not trigger occurrence of delayed maturity. However, a density of 8 adults per 0.3 m produced a significant increase in the number of green leaves retained on plants at maturity (i.e., delayed maturity). There was no effect of mechanical pod removal on green leaf retention. The lack of a significant positive correlation between mechanical pod removal and green leaf retention indicates the involvement of mechanism(s) other than reduced pod load in the occurrence of soybean delayed maturity.
20世纪70年代在巴西大豆品种——大豆（Glycine max (L.) Merril）上开展的研究表明，红带蝽（Piezodorus guildinii (Westwood)）是导致该作物成熟延迟的主要原因。这种蝽类物种最近已成为美国南部大豆的一种严重害虫，而关于其与成熟延迟紊乱发生之间的关联，人们所知甚少。此外，蝽类导致大豆成熟延迟背后的机制仍然未知。据信，在豆荚发育阶段蝽类取食会导致豆荚-种子负载量减少，从而改变源-库比，最终导致成熟延迟。为了确定引发大豆成熟延迟的红带蝽阈值，在大豆生长的R4至R5阶段进行了不同红带蝽侵染水平（每0.3米0、2、4和8只成虫）的试验。此外，为了确定大豆成熟延迟是否完全是由于豆荚负载量减少所致，对田间种植的大豆进行了不同程度机械去除豆荚（0、25、50和75%）的试验。每0.3米多达4只成虫的红带蝽密度并未引发成熟延迟的发生。然而，每0.3米8只成虫的密度使成熟时植株上保留的绿叶数量显著增加（即成熟延迟）。机械去除豆荚对绿叶保留没有影响。机械去除豆荚与绿叶保留之间缺乏显著的正相关，这表明在大豆成熟延迟的发生过程中，除了豆荚负载量减少之外，还有其他机制参与其中。
