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Riptortus pedestris (Fabricius) and Halyomorpha halys (Stål) cause injury to soybeans by piercing and sucking pods and seeds. Growers believe that new damage decreases near to harvest despite the occurrence of these bugs at that time. As this question has never been assessed, we evaluated two diets: a) mature soybean pods (dried shell + dried soybean seeds) and b) dried soybean seeds for the two bugs by assessing their biological, behavioral, and morphological attributes on each diet in laboratory. While nymphs of both species were able to develop and adults able to reproduce on the tested diets, bugs fed on pods had longer development times and 2.2 to 5.0 times higher mortality rates than bugs fed on seeds. Furthermore, adult longevity of R. pedestris and H. halys fed on pods was 8.4 and 7.5 days shorter, respectively, than that of bugs fed on seeds. However, pod feeding had no effect on adult fecundity or egg viability. In a behavioral choice test, adult R. pedestris preferred seeds over pods and probed seeds longer than pods. On average, adult H. halys also preferred seeds over pods, although 15.6% of H. halys showed the reverse, preferring pods over seeds. The proboscis length and estimated depth of stylet penetration into the host tissue of both nymphs and adults of both species was much greater than the thickness of the pod shell, suggesting that mouthpart structure does not explain the negative effects of pods vs. seeds. In conclusion, mature soybean pods were found to be a suitable food source for both R. pedestris and H. halys despite some negative effects, and thus careful attention should be paid to the population levels of these two bugs approaching harvest to reduce economic damage in soybean.

Ralstonia solanacearum causes bacterial wilt of solanaceous crop plants including brinjal, a most devastating disease in humid tropic. A survey was conducted on the status of bacterial wilt incidence and severity in major brinjal growing areas and to characterize the isolates of R. solanacearum causing bacterial wilt of brinjal in Bangladesh. The wilt incidence was recorded maximum (22.52) in Rangpur followed by Jessore (20.56) and Panchagarh (20.0) while the lowest wilt incidence was recorded in Jamalpur (6.12). On the contrary, the wilt severity was recorded highest (4.00) in Jhinaidah and the lowest (2.80) was recorded in Jamalpur followed by Jessore (2.93) at the time of survey. The isolates of R. solanacearum were obtained from different locations surveyed were arranged in seven groups based on the location. Gram's staining and Potassium hydroxide solubility test revealed that all groups of R. solanacearum isolates are gram negative. The isolates of R. solanacearum fermented four basic sugars (Dextrose, sucrose, manitol and lactose). These results of all biochemical tests in combination with the pathogenicity test confirmed the isolates were R. solanacearum causing bacterial wilt of brinjal. All groups of R. solanacearum isolates were found virulent producing pink or light red color or characteristic red center and whitish margin on TZC medium after 24 hours of incubation. On the biovar test clearly revealed that all groups of R. solanacearum isolates oxidized disaccharides (Sucrose, lactose, and maltose) and sugar alcohols (manitol, sorbitol and dulcitol) within 3-5days and confirmed biovar as III. Pathogencity test on tomato and chilli indicating wide host range of R. solanacearum isolates and categorized them in race 1. Therefore, it may be confirmed that R. solanacearum causing bacterial wilt of brinjal in Bangladesh belong to Biovar III and Race 1.

Oviposition patterns of the diamondback moth (DBM), Plutella xylostella L. (Lepidoptera: Plutellidae), differ between common cabbage (Brassica oleracea L. var. capitata) and Chinese cabbage (Brassica rapa L. var. pekinensis) (Brassicaceae) host plants. This study shows that the moth prefers to oviposit on adaxial rather than abaxial leaf surfaces and petioles of both host plants. More eggs were laid in leaf veins than on leaf laminas of both host plants, especially in Chinese cabbage, where 94.6% of eggs were laid in veins. On Chinese cabbage, very few eggs were laid in clusters (≥2 eggs), whereas on common cabbage approximately 30% of eggs were laid in groups of 2 or more eggs. Removal of wax from common cabbage leaves dramatically increased the number of eggs laid singly on the leaf lamina of treated plants, suggesting that leaf waxes affect how eggs are distributed by ovipositing DBM. Eggs were most susceptible to removal by rainfall from the plant surface immediately (<1 h) after oviposition and when close to hatching (>72h old) whereas they were least susceptible 24 h after oviposition. Eggs laid on common cabbage plants were more susceptible to simulated rainfall than eggs laid on Chinese cabbage plants. On common cabbage plants, egg susceptibility to rainfall on different plant parts ranked adaxial leaf surfaces>petioles = abaxial leaf surfaces>stem, but there was no difference in egg susceptibility to rainfall on the various plant parts of Chinese cabbage. Furthermore, on common cabbage plants, eggs laid on both adaxial and abaxial leaf surfaces were afforded significant protection from the effects of rainfall by leaves higher in the plant canopy. On common cabbage plants, oviposition patterns reduce the potential impact of rainfall on eggs, possibly reducing the effect of this important abiotic mortality factor in the field.