Evaluation of Rice Landraces for Brown Planthopper Resistance Based on Phenotypic Reactions and Biochemical Attributes

Brown planthopper (BPH), [Nilaparvata lugens (Stål.)] is an economically important pest of rice (Oryza sativa L.) throughout Asia, where the damage caused by nymphs and adults, especially during post-tillering to milking stages, significantly reduces grain yield. There is, thus, a pressing need to develop varieties that are resistant to BPH. In this study, the reaction of various rice landraces from Indian origin were assessed (both phenotypically and biochemically) in response to BPH infestation. It was found that the landraces, viz. Badshabhog, Gamra, Haldichuri, Janglijata, Kalabhat, Khara, Adanshilpa, Chikonmashuri, Kerala sundari and Lal dudheshwar exhibited resistance to BPH consistently along with the standard check Ptb33, for three consecutive years under both greenhouse and open-field conditions. These phenotypically resistant rice landraces including Ptb33 exhibited lowest feeding rate, least nymphal and adult preference, minimum survival and higher frequency (%) of unhatched eggs when compared with the susceptible check (Swarna). Higher levels ascorbic acid, oxalic acid (OA), crude silica (CS), while lower levels of phenols, reducing sugar and total free amino acid (TFA) were expressed in un-infested resistant and moderately resistant landraces. The resistant plants exposed to herbivory by BPH produced higher levels of phenolic compounds, potassium and TFA than plants of susceptible cultivar Swarna. The feeding rate, settling behaviour and survivability of BPH correlated significantly and negatively with OA and CS, whereas the latter showed a significant and positive correlation with egg hatchability.

Plant chemicals affect trade-offs between adult preference and larval performance of the rice water weevil, Lissorhoptrus oryzophilus

Herbivores use plant chemicals for host-plant selection to maximize their own and/or offspring performance. Since host plants that are optimal for mother and offspring are often different and spatially/temporally separated, how plant chemicals affect trade-offs between adult preference and larval performance remains unclear. We found that adults of the rice water weevil (Lissorhoptrus oryzophilus), one of the most important pests on rice in the world, preferred volatiles from barnyard grass over rice, tended to feed and oviposit on barnyard grass compared with rice. In contrast, larvae performed better on rice roots than on barnyard grass roots. Chemical analysis further show that rice roots had higher nitrogen and soluble sugar but lower lignin and cellhouse contents than barnyard grass. Together, these results suggest that violate, nutritive and defensive chemicals could jointly determine trade-offs of the adult preference and larval performance on these two hosts. As developing chemical-based technology is one of the main approaches for control of pest insects, our findings may also contribute to the future efforts for management of the rice water weevil.

Including Caregivers in the Community Aging in Place, Advancing Better Living for Elders Program

Older adults frequently turn to informal caregivers for support to age independently in their home as long as possible. Yet, many evidence-based programs designed to support aging in place do not include caregivers, including the well-known Community Aging in Place, Advancing Better Living for Elders (CAPABLE) program. The purpose of this qualitative study was to adapt CAPABLE to include caregivers using a grounded theory approach. Data collection occurred with stakeholders from an Area Agency on Aging (AAA) in Pennsylvania. Two, 60-minute focus groups were conducted with frontline providers (n=7) and administrators (n=7). Eight, 30-minute individual interviews were conducted with AAA consumers including older adults and their caregivers. Constant comparative analysis of the data were completed using NVivo 12 Pro. Stakeholders described three considerations for adapting CAPABLE to include caregivers: older adult preference and caregiver willingness, clear guidelines and expectations, and hands-on training. Older adults and caregivers recognized the need to “allow them to decide when and why family should be involved in the program.” Frontline providers and administrators explained the importance of “determining whether older adults and caregivers should have shared or separate goals for the program.” All stakeholders expressed that including caregivers would “reaffirm the hands-on training like fall prevention.” These perspectives shed light on how and why to include caregivers in CAPABLE. Information gleaned from this study may help researchers think about ways in which to adapt other evidence-based programs to include caregivers, and help healthcare providers target and support caregivers in the delivery of their services.

Infants look longer at colours that adults like when colours are highly saturated

The extent to which aesthetic preferences are ‘innate’ has been highly debated (Reber, Schwarz, & Winkielman, Personality and Social Psychology Review, 8(4), 364–382, 2004). For some types of visual stimuli infants look longer at those that adults prefer. It is unclear whether this is also the case for colour. A lack of relationship in prior studies between how long infants look at different colours and how much adults like those colours might be accounted for by stimulus limitations. For example, stimuli may have been too desaturated for infant vision. In the current study, using saturated colours more suitable for infants, we aim to quantify the relationship between infant looking and adult preference for colour. We take infant looking times at multiple hues from a study of infant colour categorization (Skelton, Catchpole, Abbott, Bosten, & Franklin, Proceedings of the National Academy of Sciences of the United States of America, 114(21), 5545–5550, 2017) and then measure adult preferences and compare these to infant looking. When colours are highly saturated, infants look longer at colours that adults prefer. Both infant looking time and adult preference are greatest for blue hues and are least for green-yellow. Infant looking and adult preference can be partly summarized by activation of the blue-yellow dimension in the early encoding of human colour vision. These findings suggest that colour preference is at least partially rooted in the sensory mechanisms of colour vision, and more broadly that aesthetic judgements may in part be due to underlying sensory biases.

Stink Bugs Nymph and Adult Biology and Adult Preference on Cultivated Crop Plants in the Southern Brazilian Neotropics

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.

Apple cultivar preferences by Hoplocampa testudinea (Hymenoptera: Tenthredinidae) in the Annapolis Valley of Nova Scotia, Canada

The European apple sawfly, Hoplocampa testudinea (Klug) (Hymenoptera: Tenthredinidae), is an economically important pest in eastern Canada. Growers can experience significant crop losses as management of this species is difficult because it is present during bloom. As a result, management strategies other than pesticides are required for this pest. Eleven commercial and experimental apple (Malus pumila Miller; Rosaceae) cultivars were studied to evaluate host resistance as a potential management strategy. Preferences were determined using field surveys of adult visitation, larval infestation of apples, damage at harvest, behavioural bioassays, and electrophysiological tests. Significant differences in visitation and infestation were observed. H. testudinea preferred “Zestar!”, “s23-06-153”, and “Pinova” over other cultivars examined. Comparison with subsequent larval counts and damage also suggest differential performance of larvae in several cases, irrespective of the adult preference. Y-tube bioassays and electroanntennography results indicate that olfaction plays a role in cultivar discrimination for this species.