Ponašanje pri gniježđenju i parenju pčele Andrena patella (Hymenoptera: Andrenidae)

This study of nesting and associated behavior patterns of Andrena patella was carried out at 27 locations with different landscape categories, from 2013 to 2016. The research areas chosen were generally flat or marshy areas. A total of 15 major nest aggregations were spotted and 120 nests were excavated. This species nests in soil, males emerge earlier than females, and mating occurred on flowers during the foraging season, in the 3rd week of May. The various nest and cell parameters showed low variability in the different years and different sites, but nest cell length, diameter and number varied significantly, as well as depth even at the same site. The nests were multi-cellular, oblique to horizontal, and cell shape was oval. The mating attempts of the pairs and copulatory behavior involved various steps which were completed in a very few seconds. The males appeared first on the flowers, near to the nesting site, and lived shorter than the females. The females started foraging in the 2nd to 3rd weeks of May and laid eggs in the 1st week of June. The adult phenology, egg placement, cell provision and larval feeding are described.Istraživanje gniježđenja i povezanih obrazaca ponašanja pčele Andrena patella provedeno je na 27 lokacija različitih krajobraznih kategorija, od 2013. do 2016. godine. Odabrana područja istraživanja općenito su bila ravna i vlažna. Uočeno je 15 velikih agregacija gnijezda, a iskopano je 120 gnijezda. U vrsta koje su bile ugniježđene na glinenom zemljištu mužjaci su se razvili prije ženki, a parenje se zbilo na cvijeću za vrijeme sezone paše, treći tjedan u svibnju. Različiti pokazatelji gnijezda i stanica pokazali su nisku varijabilnost u različitim godinama i na različitim lokacijama, no dužina stanica saća, njihov promjer i broj statistički su se znakovito razlikovali čak i na istom mjestu. Gnijezda su bila multistanična, kosa do vodoravna, a oblik stanica ovalan. Pokušaj parenja i kopulacijsko ponašanje uključili su različite faze koje su završene u nekoliko sekunda. Mužjaci su se prvi pojavili na cvijeću, blizu mjesta za gniježđenje, i živjeli su kraće od ženki. Ženke su počele s pašom drugi i treći tjedan svibnja, a jajašca su položile prvi tjedan u lipnju. Opisani su oblici odraslih jedinki, polaganje jaja, opskrba stanica i hranjenje ličinki

Studies of the silkworm enzyme activity and their correlations with economic variables

The experiment was conducted to analyse the larval performance and economic traits of bivoltine silkworm breeds of silkworm (SK-1, SK-6, SK-22, SK-28, SK-33, CSR4, CSR2, NB4D2, DUN6 and APS4) during spring season. The haemolymph total protein, succinate and gultamate dehydrogenase activities were estimated and their correlation with economic traits were also worked out. The results of the study confirmed that among ten bivoltine silkworm breeds, highest haemolymph SDH activity of 3.47 µmoles/ml/mgprotein/min was recorded in the silkworm breed SK1 and least SDH activity of 1.58 µmoles/ml/mg protein/min was recorded in the breed APS4. The highest peak of succinate dehydrogenase activity of 2.65 µmoles/ml/mg protein/min was observed on 7th day of the 5th instar and lowest peak of succinate dehydrogenase activity of 2.39 µmoles/ml/mg protein/min was observed on 4th day of the 5th instar. GDH activity of 0.46 µmoles/ml/mg protein/min was recorded highest in the silkworm breed SK1 and lowest of 0.15 µmoles/ml/mg protein/min was recorded in silkworm breed APS4. The highest peak of haemolymph GDH of 0.36 µmoles/ml/mg protein/min was recorded on 7th day of 5th instar and lowest peak of 0.26 µmoles/ml/mg protein/min was recorded on 4th day of 5th instar. The correlational studies revealed that haemolymph total protein, SDH and GDH were found to be positively corelated with yield by weight and number (cocoon), weight of mature larvae, shell weight ,cocoon weight, shell ratio percent, silk productivity, rate of pupation, fecundity, raw silk percentage  and length of filament. Thus, the study revealed that silkworm breeds like SK1, SK6, SK22 and SK28 as productive breeds and hence may be used for future breeding programmes for evolution of new robust silkworm breed

Evaluation of seedling age and nutrient sources on phenology, yield and agrometeorological indices for sweet corn (Zea mays saccharata L.)

The field experiment was conducted during Kharif season of 2020 at Agronomy farm of Faculty of Agriculture, Wadura, SKUAST-K to study the influence of age of seedling and sources of nutrients on phenology, yield and agrometeorological indices for sweet corn. The experiment included two factors viz. age of seedlings (12, 22 and 32 days old seedling) and sources of nutrients (control, RDF, 50 percent RDF + FYM @ 12 t ha−1, 50 percent RDF + vermi-compost @ 4 t ha−1 and 50 percent RDF + poultry manure @ 2 t ha−1) tested in RCBD with three replications. Transplanting 12 days old seedlings required maximum number of days to attain different phenological stages, thereby accumulated maximum heat units followed by 22 days old seedlings. While as transplanting 22 days old seedling recorded significantly highest HUE, HTUE, PTUE and HyTUE and consequently resulted in the highest green cob and biological yield compared to other ages of seedlings. Among various sources of nutrients, application of 50 per cent RDF + poultry manure @ 2 t ha−1 took maximum number of days to attain various phenophases thereby accumulated maximum heat units and registered highest HUE, HTUE, PTUE and HyTUE followed by application of 100 per cent RDF

Estimation of yield, phenology and agro-meteorological indices of Quality Protein Maize (Zea mays L.) under different nutrient omissions in temperate ecology of Kashmir

The major yield governing factors especially under rainfed ecosystem are the agro-meteorological indices. Hence, an experiment was conducted in 2021 kharif season to examine the impact of nutrient omission on phenology, yield and agro-meteorological indices of Quality Protein Maize (QPM) under the North Western Himalayas of India at the Agronomy farm of FoA (Faculty of Agriculture), Wadoora, Sopore, SKUAST-Kashmir. Eight treatments were used in the experiment viz. (T1-Absolute control, T2-N120P75K40, T3-N120P75K40Zn5S10, T4-P75K40Zn5S10 (-N), T5-N120K40Zn5S10 (-P), T6-N120P75Zn5S10 (-K), T7-N120P75K40S10 (-Zn) and T8-N120P75K40Zn5 (-S)), using a randomized complete block design with three replications. Results demonstrated that recommended dose of fertilizer plus zinc and sulphur (T3-N120P75K40Zn5S10) noted higher grain (9.78 t ha−1) and biological (22.05 t ha−1) yield, a longer period of time to reach various phonological stages thereby achieved maximum heat units or growing degree days (GDD), heliothermal units (HTU), photo-thermal units (PTU), pheno-thermal index (PTI) and heat use efficiency (HUE). Nitrogen was the most limiting nutrient thereby accumulating least heat units and HUE. The agrometeorological indices could be therefore helpful in predicting the phenology and maize yield. The outcomes of the experiment showed that using the recommended fertilizer dosage plus zinc and sulphur in QPM should be adopted to attain higher yield under the North Western Himalayas of India, However, additional agro-ecological study is required to further validate the findings