Implementation of Soybean in Cotton Cropping Sequences for Management of Reniform Nematode in South Texas

Abstract

Rotylenchulus reniformis Linford & Oliveira is increasing in incidence in cotton‐growing areas throughout the southern USA east of New Mexico. Cotton (Gossypium hirsutum L.) cultivars resistant to R. reniformis are currently unavailable. Management depends on a crop sequence with nonhosts of the nematode. In South Texas, the sequence of cotton with grain sorghum [Sorghum bicolor (L.) Moench] or corn (Zea mays L.) has become a standard practice. To improve farm efficiency, the implementation of rotation crops that are economically superior to grain sorghum is desirable. Eighteen cultivars of soybean [Glycine max (L.) Merr.] were tested in nonfumigated and in fumigated sandy loam soil infested with R. reniformis to evaluate nematode resistance of soybean under field conditions. Shank application of 1,3‐dichloropropene at a 38‐cm depth reduced R. reniformis population densities at the 15‐ to 60‐cm depth compared with preseason counts. The effect of each soybean cultivar on the growth and yield of a subsequent cotton crop was compared with the impact of grain sorghum and fallow. High‐yielding cultivars of soybean (HY574, Padre, DP7375RR, and NK83‐30) with reniform nematode‐suppressing potential were identified among cultivars within maturity groups 5, 6, 7, and 8. In contrast, cotton yields following the susceptible cultivars Santa Rosa‐R, Vernal, and DP6880RR were on average 25% lower than those following grain sorghum. The enrichment of cotton sequences with reniform nematode‐resistant soybean cultivars is viable when the proper cultivars are chosen, whereas the use of reniform nematode‐susceptible soybean cultivars is discouraged. The effective use of R. reniformis‐resistant soybean cultivars to manage R. reniformis in cotton will depend on a number of additional economic parameters not studied in these experiments.

Vertical Distribution of Heterodera schachtii under Susceptible, Resistant, or Tolerant Sugar Beet Cultivars

“…Such recolonization of soil was found for other cyst nematodes (e.g., in potato cyst nematodes; 1). The observation of this rapid recolonization was somewhat contrary to the aforementioned Rotylenchulus reniformis, which colonized 1,3-D-treatedlayers quickly if soil was treated only to a depth of 38 cm but was somewhat slower to colonize soil treated with 1,3-D to a depth of 60 cm (22,23). Our observation of recolonization during one vegetation period in the LL.…”

“…This was expected because such observations were made with other nematodes as well (e.g., R. reniformis; 22,23). The fact that plant canopy diameter 5 weeks after planting predicted WSYs in the susceptible Beretta was a reminder of the importance of protection of a susceptible cultivar against the nematode during early plant growth.…”

Biotic interactions, ecological knowledge and agriculture

“…It appears that shifts can happen over relatively short time frames; for example, the effects of long-term crop management on nematodes, other than plant feeders, disappeared within a year of disruptive soil management (Berkelmans et al 2003). Nonetheless, crop rotations can be an effective nematode management tool through a combination of the inclusion of non-host crops or varieties, use of nematode-suppressive cover crops and residues, and stimulating changes in soil communities through organic matter management (Caamal-Maldonado et al 2001;Vargas-Ayala & Rodriguez-Kabana 2001;Pyrowolakis et al 2002;Zasada & Ferris 2004;Snapp et al 2005;Westphal & Scott 2005). Similarly, the species composition of fallows in shifting cultivation and bush-fallow systems can also be manipulated to suppress key plant parasitic nematodes (Adediran et al 2005).…”

Nitrogen Contribution of Peanut Residue to Cotton in a Conservation Tillage System

“…More recent research in the southern U.S. involving summer cash legumes, e.g., soybean or peanut grown in rotation with a cotton crop, has primarily focused on nematode management. Researchers have focused on the potential nematode suppressive effect of a summer cash legume (Westphal and Scott, 2005) and not the N requirements of cotton following a particular summer cash legume.…”