Honeybee nutrition and pollen substitutes: A review

Like other invertebrates, honey bees too are poikilothermic animals; they cannot regulate their body temperature and they have to undergo a period of inactivation when atmospheric temperature is un-tolerable. During this period, their nutritional requirements and metabolic activities are minimized due to highly restricted foraging activities. The egg-laying by queen and rearing of unsealed and sealed brood are decreased, however their extent is governed by the quantum of stored food available. The problems of deleterious influence of adverse weather conditions and non-availability of bee flora all round the year, in a particular locality, have been realized by the researchers/beekeepers and migration concept has been developed to solve this problem. But again, migration itself is not an easy task. The provision of artificial feeding as an alternate of migration. Scientists all over the world have formulated different artificial food recepies for bees on the basis of nutrient composition of honey and pollen, acceptability, palatability, digestibility and affordability of ingredients. This may help to maintain all colony parameters enough to derive maximum advantage of forthcoming floral rich season. However, a standard balanced diet for commercial beekeeping that is accepted worldwide is still awaited.     

Influence of different types of explants in chickpea regeneration using thidiazuron seed-priming

Journal of Plant Research - A comparative regeneration of three types of explants prepared from axillary meristems, plumular apices and hypocotyls of chickpea (Cicer arietinum) was carried out...     

Zum Brutvorkommen des Girlitzes,Serinus serinus (L.), im Ostbaltikum

Ohne Zusammenfassung     

Seasonal pattern of tartaric acid metabolism underlying the phasic development inTamarindus indica L.

Tartaric acid is synthesized on light in the leaves ofTamarindus indica L. and is translocated to the flowers during flowering seasons. The translocation of this acid to fruits keeps peace with their growth rate. The decline of the tartaric acid content per unit fresh weight in mature fruits is not due to their utilization or conversion, but largely due to the setting up of the seeds which are devoid of any tartaric acid. Tartaric acid content in both the leaves and fruits show variation in different seasons, while malic acid does not show any change excepting a small increase in March.     

Foraging behaviour of Scymnus coccivora Ayyar against cotton mealybug Phenacoccus solenopsis Tinsley

Predation is one of the significant biotic mortality factors reducing the insect pest population as functional response and the numerical response of the predator are the key factor regulating the population dynamics of predator prey species. This study is aimed to evaluate the functional response of all the developmental stages of Scymnus coccivora Ayyar (Coleoptera: Coccinellidae) against the different densities of cotton mealybug, Phenacoccus solenopsis (Tinsley) (Hemiptera: Pseudococcidae) and the numerical response of female predator. Experiments were carried out in controlled environment laboratory conditions at 25 ± 1 °C temperature, 60 ± 5% relative humidity and photoperiod of 16 h. Number of eggs consumed, number of eggs laid and the Efficiency of Conversion of Ingested food (ECI) were recorded daily. Results from the study revealed that all the developmental stages of S. coccivora exhibited a Type II response. Different parameters such as attack rate (a’), handling time (T_h) and the maximum rate of predation were estimated using Roger’s random attack equation and Holling Disc equation in which Rogers random attack equation was found best fit. Female has shown the highest attack rate (a’) followed by IV^th instar grub, male, III^rd, II^nd and I^st instar grub. With low handling time, IV^th instar grub has shown maximum predation rate of 76.40 per day followed by female (75.86), male (58.79), III^rd (22.84), II^nd (19.65) and I^st instar grub (15.39). The numerical response increase was curvilinearly related to different prey densities with the highest number of eggs (11.8 ± 3.44) produced at highest prey density (160). The Efficiency of Conversion of Ingested food (ECI) was highest (64.49 ± 8.03) at prey density of 10. Understanding the factors that lead to variation in functional response of predator in natural population will advance our understanding of the effects of predation on individual and the effectiveness of coccinellid predators as biocontrol agent against cotton mealybug.     

Affinity chromatography of estrogen- and progesterone-binding proteins of human uterus

The purification of estrogen- and progesterone-binding proteins of human uterus by employing affinity resins coupled with steroid-bovine serum albumin conjugates, led to the isolation of preparations with estrogen- and progesterone-binding sites havingK _d values in the range of 0.96 to 1.20 × 10^-9 M. These were different from theK _d values of 10^-10 M and 10^-8 M obtained for two types of binding sites present in the crude cytosolic and nuclear fractions. The purified proteins sedimented on sucrose gradient withS values in the range of 3.6–4.4. The cytosolic and nuclear estrogen- and progesterone-binding proteins, thus purified, showed differences in specificity of binding to the hormone. While the cytoplasmic proteins were more specific in their binding to estradiol or progesterone, the nuclear proteins bound Cortisol with equal or moderate affnity. These results demonstrate the presence of distinct physiological forms of estrogen- and progesterone-binding proteins in the cytoplasm and nucleus, thus pointing to the importance of both these compartments in hormone action.