Rice weevil, Sitophilus oryzae L. (Coleoptera: Curculionidae) is a widely distributed and major insect pest of rice that causes considerable losses to both husked and unhusked rice grains. Plant-based pesticides are alternative to synthetic pesticides in managing stored product pests owing to their severe hazardous effects. Thus, locally available plant leaf crude extracts i.e., neem (Azadirachta indica A. Juss 1830), turmeric (Curcuma longa L. 1753), and mint (Mentha longifolia L. Huds. 1762) were investigated at 2 % (w/w) concentration against S. oryzae in unhusked and husked rice. Adult mortality was recorded at 24, 48 hours, and seven days after the application whereas, population build-up was recorded at 1-, 2-, and 3-months intervals. Overall and grain weight loss was also recorded at the end of the experiment. In husked and unhusked rice, the highest mortality percentage was observed in turmeric powder (93.30 %) and neem (80.00 %), respectively. In comparison to plant extracts, relatively higher population growth of S. oryzae was recorded in control husked and unhusked rice. At the end of the 3rd month, the highest and lowest population in husked rice grains was recorded in control (70.67 ± 3.18) and turmeric treatments (18.00 ± 2.65), respectively, whereas control and neem treatments exhibited the highest (83.67 ± 3.28) and lowest (39.67 ± 2.33) populations in unhusked rice. The lowest grain weight loss in husked and unhusked rice was recorded in turmeric (9.33 %) and neem (16.67 %), respectively. Thus, turmeric and neem extracts should be investigated on large scale under commercial warehouses for the management of S. oryzae in husked and unhusked rice.

Livestock biogas slurry is an effluent containing nutrients such as ammonium and phosphate that are released by the industries. Therefore, recovery and reuse of ammonium and phosphorus is highly necessary. In recent years, many studies have been devoted to the use of different multivariate statistical analyses to investigate the interrelationship of one factor to another factor. The overall objective of this research study was to understand the significance of phosphate and ammonium recovery from biogas slurry using the multivariate statistical approach. This study was conducted using a range of salts that are commonly found in biogas slurry (ZnCl2, FeCl3, FeCl2, CuCl2, Na2CO3, and NaHCO3). Experiments with a biogas digester and aqueous solution were conducted at pH 9, with integration with NH4+, Mg2+, and PO43− molar ratios of 1.0, 1.2, and 1.8, respectively. The removal efficiency of ammonium and phosphate increased from 15.0% to 71.0% and 18.0% to 99.0%, respectively, by increasing the dose of respective ions K+, Zn2+, Fe3+, Fe2+, Cu2+, and CO32−. The elements were increased from 58.0 to 71.0 for HCO3−, with the concentration increasing from 30 mg L−1 to 240 mg L−1. Principal component, regression, path analysis, and Pearson correlation analyses were used to investigate the relationships of phosphate and ammonium recovery under different biochar, pyrolysis temperature, element concentration and removal efficiencies. Multivariate statistical analysis was also used to comprehensively evaluate the biochar and struvite effects on recovery of ammonium and phosphate from biogas slurry. The results showed that combined study of multivariate statistics suggested that all the indicators positively or negatively affected each other. Pearson correlation was insignificant in many ionic concentrations, as all were more than the significant 0.05. The study concluded that temperature, biochar type, and varying levels of components, such as K+, Zn2+, Fe3+, Fe2+, Cu2+, CO32−, and HCO3−, all had a substantial impact on P and NH4+ recovery. Temperature and varying amounts of metal salts enhanced the efficacy of ammonium and phosphate recovery. This research elucidated the methods by which biochar effectively reuses nitrogen and phosphate from biogas slurry, presenting a long-term agricultural solution.

Callosobruchus spp. are global serious pests of pulses. Therefore, two studies were carried out to determine their distribution in three ecological zones of the Sindh, Pakistan along with their damage potential to major pulses. Survey was conducted from Zone-one (Ghotki, Sukkur and Larkana districts), Zone-two (Hyderabad, Mirpur Khas and Shaheed Benazirabad districts) and Zone-three (Karachi district) during March – April 2020. Grain samples of main pulses i.e., chickpea (channa), field pea (matar), cowpea (lobia), green lentil (moong) and daal channa were collected from three locations of each district and brought to Stored Grain Research Laboratory, Department of Entomology, Faculty of Crop Protection, Sindh Agriculture University, Tandojam for further examination. Three pulse beetle species i.e., C. maculatus, C. chinensis and C. analis were identified from the collected pulse samples as the highest populations of adults, eggs, grubs and pupae was recorded from moong, followed by lobia and gram. No population of pulse beetle was recorded from daal channa and matar. Callosobruchus maculatus was the most dominant species at all sampling as higher beetle populations were recorded from Mirpur Khas and Sukkur districts. Therefore, both these strains were further evaluated for their feeding preference and weight loss assessment on various pulses i.e., gram (chickpea), lobia (cowpea), moong (green gram) and daal channa (yellow lentil) in no-choice under laboratory conditions. C. maculatus showed a significant feeding preference among pulses with lobia and gram being the most preferred, whereas daal channa was the least preferred, hence suffered highest and lowest weight loss, respectively. Therefore, proper storage and quarantine measures are suggested to be taken in the transportation and storage of pulses to restrict the spread and damage of pulse beetles.

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M aize holds a key position as cereal along with wheat and rice to fight the war against hunger in the world (Pingali, 2001). However, in recent years, fall armyworm (FAW) Spodoptera frugiperda J.E. Smith (Lepidoptera: Noctuidae) has pose a great threat to production of maize throughout the world Abstract | Fall armyworm (FAW) Spodoptera frugiperda has shown invasive characteristics, especially against maize production in African and Asian countries including Pakistan. Therefore, understandings of its biological features in introduced locations could improve understanding of its invasive features, which is necessary for better management. Accordingly, life table and fertility schedule studies of FAW were conducted under laboratory conditions on maize leaves and stems. Three cohorts comprised of 131, 112 and 105 eggs of similar age were used for both leaves and stems. The results indicated that maximum mortality of FAW in both maize stems and leaves were recorded in pupa and 1 st larval instar, respectively whereas, maximum survival was recorded in 4 th and 5 th larval instars. Almost, similar male to female sex ratio was recorded in leaves and stems with higher female longevity in leaves than stems. No significant difference was recorded in approximate and corrected generation time of FAW between leaves and stems. Innate capacity of increase (r c ) and intrinsic rate of natural increase (r m ) recorded on stems (0.1237±0.0032 and 0.1248±0.0033, respectively) were higher than leaves (0.1027±0.0025 and 0.1034±0.0026, respectively). Finite rate of increase (λ), doubling time (DT) and net reproductive rate (R o ) observed on maize stems (0.3363±0.0086, 5.61±0.14 days and 143.29±12.27 offspring/individual, respectively) were higher than those observed on leaves (0.2791±0.0069, 6.76±0.16 days and 69.63±6.22 offspring/individual, respectively). As FAW showed better population and reproductive parameters on maize stems than leaves, it should be managed as early as possible to restrict losses to maize before establishment of perfect stems.