Timing and order of different insecticide classes drive control of Drosophila suzukii; a modeling approach

The spotted-wing drosophila, Drosophila suzukii Matsumura, is an invasive pest causing significant damage to soft skinned fruits. Control of D. suzukii is critical since there is no tolerance for infested fruit in the market. While most insecticides control one or more D. suzukii life-stages (e.g., egg, larvae, and adult), the impact of insecticides that are toxic to immature stages  is unclear on the subsequent generation of a field population. Insecticides were applied at field recommended rates on cherries and blueberries in the laboratory to determine immature D. suzukii mortality. Spinetoram, cyantraniliprole, malathion, methomyl, spinosad, and phosmet resulted in relatively high mortality of all immature life stages. Zeta-cypermethrin, cyclaniliprole, and fenpropathrin resulted in lower mortality of egg and all larval instars. Malathion was also applied to lowbush blueberries with different fruit sizes (small, medium, and large) in the laboratory and there was no statistical difference in mortality rates depending on fruit sizes. Mortality data from the laboratory experiments were used to parameterize a refined D. suzukii population model. The model revealed that the timing and order of different insecticide classes are important to control D. suzukii population. Model runs that included early applications of more effective insecticides resulted in high immature mortality and greater reduction of D. suzukii populations compared to treatments applied later.

     

Productivity and nutrient uptake of newly released wheat varieties at different sowing times under poplar plantation in north-western India

Standardisation of cultural practises is one of the primary objectives to make the system ecologically sustainable and economically viable. In this context, the present study was conducted to optimise the time of sowing in relation to newly released wheat varieties under 4–6 year old poplar block plantation. Six widely grown wheat varieties (PBW 502, PBW 343, WH 542, PDW 274, PBW 509 and PBW 373) were intercultivated during three consecutive crop growth seasons at three times of sowing (mid November, late November and mid December) under block plantation of poplar (Populus deltoides Bartr.) clone G-48. The grain yield and nutrient uptake of wheat varieties was higher in open conditions than under the trees. The wheat variety PBW 502 out yielded the rest of wheat varieties over different sowing times. The highest grain yield was recorded when crop was sown during mid November over the 3 years. Thus adoption of PBW 502 under poplar plantation would substantially improve the overall productivity of the system without any additional input cost. All the varieties performed better when sown early compared to one-month delay. The various growth parameters like tiller height and number, spike length and 100 grain weight contributed significantly towards higher grain yield in early sown conditions (mid November) under poplar irrespective of its age of plantation. The nutrient uptake (N, P and K) by wheat straw and grain was higher in early sown crop with longer growth span than the late sown crop. The higher quantity of N, P and K was removed from soil by PBW 509, PBW 373 and PBW 343, respectively.     

Micropropagation of Vegetable Rennet (Withania coagulans [Stocks] Dunal)—A Critically Endangered Medicinal Plant

Withania coagulans (Stocks) Dunal (Solanaceae), popularly called vegetable rennet, is a critically endangered and highly valued medicinal plant. Overexploitation and reproductive failure forced the plant species toward the verge of complete extinction. We describe here the development of a simple, rapid, and cost effective in vitro micropropagation system for W. coagulans for mass-scale production of true-to-type plantlets using nodal shoot segments. Exactly 95.5 ± 0.34% explants responded within 8–10 days (d) and produced multiple shoot buds (4.1 ± 0.10 shoots of 2.95 ± 0.15 cm length) on 0.8% agar-gelled Murashige and Skoog's (MS) basal medium supplemented with 8.88 μM 6-benzylaminopurine (BAP), 0.57 μM indole-3-acetic acid (IAA), and additives (100 mg L^?1 L-ascorbic acid, 25 mg L^?1 each citric acid, adenine sulphate, and L-arginine). The shoots in cultures were multiplied by repeated transfer on MS medium with 4.44 μM BAP, 0.57 μM IAA, and additives. Further cultures were multiplied on a large-scale through the subculturing of shoot clumps differentiated in vitro, on MS medium supplemented with 1.11 μM BAP, 0.57 μM IAA, and additives. Maximum number (19.1 ± 0.28) of healthy (6.15 ± 0.25 cm) and viable shoots differentiated on this medium. The microshoots were rooted both in vitro and ex vitro. Exactly 67.3 ± 1.01% microshoots rooted in vitro within 25–30 d on agar-gelled half-strength MS salts supplemented with 29.52 μM indole-3-butyric acid (IBA) and 200 mg L^?1 of activated charcoal (AC). Alternatively, 73.8 ± 0.65% cloned shoots rooted on sterile soilrite (soilless compost and soil conditioner) under ex vitro conditions after pulse treatment with 2.46 mM IBA for 300 s. The clones of W. coagulans were hardened in a greenhouse within 40–45 d by slow and gradual exposure of plantlets from high relative humidity (RH; 70–80%) and low (26 ± 2°C) temperature to low RH (40–50%) and high (34 ± 2°C) temperature. The hardened plantlets were transferred to soil and stored in agro-net house with more than 90% survival rate. Replacement of pure and laboratory grade sucrose with commercial grade sugar, use of less expensive commercial grade agar-agar in culture medium, higher rate of shoot proliferation, single step ex vitro rooting, and hardening of plantlets in the greenhouse are advantageous features of the protocol. The micropropagation protocol defined here is reproducible, easy to follow, and would be helpful in large-scale restoration programs through true-to-type mass-multiplication of W. coagulans.     

Soil greenhouse gas emissions from agroforestry and other land uses under different moisture regimes in lower Missouri River Floodplain soils: a laboratory approach

Changes in land use management practices may have multiple effects on microclimate and soil properties that affect soil greenhouse gas (GHG) emissions. Soil surface GHG emissions need to be better quantified in order to assess the total environmental costs of current and possible alternative land uses in the Missouri River Floodplain (MRF). The objective of this study was to evaluate soil GHG emissions (CO₂, CH₄, N₂O) in MRF soils under long-term agroforestry (AF), row-crop agriculture (AG) and riparian forest (FOR) systems in response to differences in soil water content, land use, and N fertilizer inputs. Intact soil cores were obtained from all three land use systems and incubated under constant temperature conditions for a period of 94 days using randomized complete block design with three replications. Cores were subjected to three different water regimes: flooded (FLD), optimal for CO₂ efflux (OPT), and fluctuating. Additional N fertilizer treatments for the AG and AF land uses were included during the incubation and designated as AG-N and AF-N, respectively. Soil CO₂ and N₂O emissions were affected by the land use systems and soil moisture regimes. The AF land use resulted in significantly lower cumulative soil CO₂ and N₂O emissions than FOR soils under the OPT water regime. Nitrogen application to AG and AF did not increase cumulative soil CO₂ emissions. FLD resulted in the highest soil N₂O and CH₄ emissions, but did not cause any increases in soil cumulative CO₂ emissions compared to OPT water regime conditions. Cumulative soil CO₂ and N₂O emissions were positively correlated with soil pH. Soil cumulative soil CH₄ emissions were only affected by water regimes and strongly correlated with soil redox potential.     

Apium graveolens PI 181714 is a source of resistance to Fusarium oxysporum f. sp. apii race 4 in celery (A. graveolens var. dulce)

Celery has little genetic diversity and is highly susceptible to the new fungal pathogen Fusarium oxysporum f. sp. apii (Foa) race 4. After screening an Apium graveolens germplasm collection for resistance to Foa race 4, we crossed celery cv. 'Challenger', which is Foa race 2-resistant but Foa race 4-susceptible and A. graveolens PI 181714, which is Foa races 2- and 4-resistant but non-celery type. After selfing F₁s, we screened the F₁S₁ for race 4-resistance and celery-type and then selfed selected F₁S₁. Greenhouse and field trials indicate that three selected F₁S₂ families (76–8-4, 76–8-27 and 76–8-36) are suitable as germplasm for celery breeders for resistance to Foa race 4. A F1S3 76–8–36-124 is either fixed or nearly so for resistance to Foa races 4 and 2. Furthermore, quantitative PCR indicates that PI 181714 is resistant, rather than tolerant, to Foa races 4 and 2, and that this resistance has been introgressed into F1S3 76–8–36-124.     

Ultimate fate of halosulfuron methyl and its effects on enzymatic and microbial activities in three differently textured soils

Halosulfuron methyl is a sulfonylurea herbicide used worldwide for weed control in sugarcane, maize, wheat, and rice production. Considering its environmental impact, this study evaluated the effects of soil type, application rate, and temperature on the dynamics of halosulfuron methyl degradation.Additionally, as soil microbes and enzymes are reliable indicators of the impacts of anthropogenic activities on soil health, the effects of halosulfuron methyl on soil enzymatic and microbial activiti...     

Comparison of Composition,Protein, Pasting,and Phenolic Compounds of Brown Rice and Germinated Brown Rice from Different Cultivars

Physical characteristics, amino acids composition, protein profiling, pasting characteristics, and phenolic compounds of brown rice (BR) and germinated brown rice (GBR) from different paddy cultivars (PB1, PS44, PB1509, PB1121, and PS5) were investigated. L* (lightness) decreased, but a* (redness and greenness) and b* (yellowness and blueness) increased with germination. Protein and ash content increased, whereas fat and amylose contents decreased with germination. GBR showed lower hardness and gumminess than BR. Foam stability and water absorption capacity from GBR flour were higher compared with BR flour. Accumulation of γ‐aminobutyric acid, histidine, arginine, proline, methionine, and acidic amino acids increased significantly with germination, and increase was related to change in accumulation of glutelin and prolamins. The accumulation of prolamins and glutelin acidic and basic subunits decreased with germination. GBR flour showed lower pasting viscosities compared with BR flour. Ferulic acid, p‐coumaric acid, and quercetin were present in both fractions of the bound form. GBR showed improved nutritional quality that varied in different cultivars. PB1121 was observed to be the best for producing GBR owing to greater changes brought in protein content, essential amino acids, catechin, chlorogenic acid, protocatechuic acid, vanillic acid, and foam stability.     

Simultaneous determination of kaempferol and quercetin in Heteropogon Contortus (L.) Beauv. by validated high-performance thin layer chromatography

Presently, the fingerprint analysis of kaempferol and quercetin has been developed simultaneously via High-Performance Thin Layer Chromatography (HPTLC) from leaves, stem, and inflorescence of Heteropogon contortus. The HPTLC method for kaempferol and quercetin was optimized with the elution of toluene: ethyl acetate: formic acid (7:3:0.5 v/v) as a mobile phase. The fingerprint analysis of kaempferol and quercetin was developed at R_f values of 0.39 and 0.24, respectively, and densitometric evaluation was done at 254 nm. The linear regression data for the calibration curve of both the compounds show a good linear relationship in the concentration range of 2–12 nanogram spot^?1. The suggested method has been validated in terms of limit of detection (LOD) and limit of quantification (LOQ), precision, specificity, sensitivity, and accuracy. Present results show that maximum amount of kaempferol and quercetin is found in leaf extracts (35.80 and 17.01 milligram/gram of dry weight, respectively) of H. contortus.     

Growth,symbiosis, productivity,and profitability of soybean at varying planting methods and nitrogen levels

A field experiment was conducted to study the effect of different planting methods (Happy Seeder sowing, Straw Chopper + Zero Tillage sowing, and conventional sowing) and nitrogen (N) levels (0%, 75%, 100%, and 125% of recommended N) on the emergence, growth, symbiotic parameters, productivity, and profitability of soybean sown after wheat harvest. Growth and symbiotic parameters were significantly better under Happy Seeder sowing and Straw Chopper + Zero Tillage sowing than conventional sowing. The seed yield, nutrient uptake, and economic returns were significantly higher under Happy Seeder sowing than other methods. The growth parameters, symbiotic parameters, biological, straw, and seed yields were increased significantly up to 100% recommended N level. The nutrient uptake increased significantly up to 100% recommended N level. Therefore, sowing with Happy Seeder after combine harvested wheat along with 100% recommended N would best optimize soybean yield and profitability.     

Evaluation of Dry Peas (Pisum sativum L.) Varieties for Seedling Vigor Indices in Eastern Montana

Genetic and environmental factors lead to a variation in yield and protein content of dry pea (Pisum sativum L.) seeds. The quality of seed, particularly seed vigor, also influences the establishment of crop and thus final grain yield. The area and production for dry peas are increasing in the Northern Great Plains but knowledge is lacking on how the pea lines/varieties differ in the seed vigor at seven leaf stage. This field and greenhouse study evaluated the eight dry pea lines/varieties for seedling vigor indices and correlated them with grain yield and protein concentrations. Significant differences were observed among the lines/varieties for nodule number plant^?1 in greenhouse, and grain yield in field conditions. The highest number of nodules plant^?1 was obtained with the line MT632, which were at par with lines MT457, and MT190. The highest Vigor Index I was achieved with line MT632 associated with their more shoot lengths as compared to other lines/varieties. The highest Vigor Index II was obtained by variety Majoret and line MT632. The variety DS Admiral yielded 5205 kg ha^?1, which was 17.4 and 33.3% higher than lines MT460 and MT190, respectively. The highest seed protein content was obtained with variety Majoret (23.4%) having highest Vigor Index II and seed yield (4940 kg ha^?1) at par with variety DS Admiral. The lowest seed protein was found with variety DS Admiral (20.3%). The line named MT190 showed lowest yield potential along with the lower protein contents also. Studies show a positive and significant correlation between biomass and Vigor Index I only. Plant nitrogen uptake was positively and significantly correlated with biomass and Vigor Index I in greenhouse only. The results also indicated that seed vigor indices did not reveal any significant correlations with dry peas yield and protein content, so more efforts are needed to evaluate varieties for higher yield and protein content during initial stages of growth in order to maximize their acreage and productivity.