Laboratory studies were conducted with Dichelops furcatus (F.), Euschistus heros (F.), and Nezara viridula (L.) (Heteroptera: Pentatomidae) aiming to evaluate nymph and adult biology and adult preference for immature reproductive structures of the cultivated plants, soybean, Glycine max (L.) Merrill (Fabaceae), wheat, Triticum aestivum L. (Poaceae), and canola, Brassica napus L. var. oleifera (Brassicaceae). Considering the survivorship for D. furcatus nymphs, it was greater on soybean and wheat, for E. heros nymphs it was greater on soybean compared to canola and wheat, and for N. viridula nymphs the survivorship was greater on soybean and canola. Dichelops furcatus nymphs developed faster on soybean and wheat, and E. heros and N. viridula nymphs developed faster on soybean and canola. Body weight at adult emergency for D. furcatus was greater on soybean and wheat, and for E. heros and N. viridula, it was greater on soybean. Adult survivorship and longevity were similar on soybean/wheat/canola for D. furcatus and N. viridula, and greater on soybean for E. heros. Reproduction and weight gain of adults were greater on soybean and wheat for D. furcatus, and on soybean for E. heros; N. viridula reproduced only on soybean and tended to gain greater body weight in this food source. As expected, soybean considering its superior nutritional quality was, in general, the best food. These laboratory studies coupled with field observations allow to conclude that the sequence of soybean/wheat/canola crops in the area studied forms a ‘green bridge’ that favor stink bug populations abundance in southern Brazilian neotropics.

The performance and preferences of the stink bug, Dichelops furcatus (F.), for spring cereals (wheat, rye, triticale, oat, and barley) were compared in the laboratory to their preferred host crop, soybean pods. Nymphs took significantly less time to reach adulthood on soybean pods compared to those fed seed heads of the five spring cereals tested. Wheat and rye yielded the longest developmental times, while nymphs fed triticale, oat, or barley developed faster, but still not as fast as those reared on soybean pods. On all foods ≥78% of nymphs reached adulthood. Adult body weight was significantly greater on soybean pods than on any of the spring cereals, and adults increased in body weight on all food sources tested. Fecundity was significantly greater for females fed soybean pods than those reared on the cereals. Egg viability was ≥66.9% except for bugs fed triticale (31.4%). In general, adult D. furcatus preferred soybean pods to seed heads of spring cereals, with wheat being preferred over the other spring cereals.

Adopting wheat that has additional aptitudes to the only function of grain production in crop-livestock integration systems may be an economical alternative for better using the vast expanse of farmland during the autumn-winter period in southern Brazil. The objective of this study was to evaluate economically the crop-livestock integration (CLI) system, in comparison to systems of grain production only. The treatments consisted of six CLI systems, containing either annual winter pasture, soil cover or dualpurpose cereals: system I (wheat/soybean and vetch/maize); system II (wheat/soybean and black oat/maize pasture); system III (wheat/soybean and black oat/soybean pasture); system IV (wheat/soybean and pea/maize); system V (wheat/soybean, dualpurpose triticale/soybean and vetch/soybean); and system VI (wheat/soybean, dual-purpose white oat/soy and dual-purpose wheat/ soybean). The treatments were repeated four times in the randomized block design. Calculation of the operational cost and net return of the production systems followed the technical coefficient matrix of the experiment and the prices of inputs and machines from the cultivation year, based on the 2016 market . Systems II and III, which had annual winter pastures, were more profitable than systems I and IV, with legume cover cropping. System VI, with white oat and double-purpose wheat, demonstrated a higher economic return when compared to the system V, with triticale. Overall, system II stood out due to its higher net return.