Characterization of Anatomical and Physiological Adaptations in Cassytha filiformis L.—An Advanced Obligate Hemiparasite on Morinda tinctoria Roxb.

A study was conducted to understand the host-parasite relationship in terms of anatomical and physiological adaptations in Morinda tinctoria Roxb. and Cassytha filiformis L. Anatomically the haustorium of Cassytha is found to have two parts, the upper haustorium and the endophyte. The former is the portion of a haustorium that lies external to the host organ, whereas the endophyte is the portion of a haustorium that penetrates host tissues. It was also observed that the host organ triggers the dedifferentiation of cortical parenchyma to develop dense cytoplasm, conspicuous nuclei and numerous starch grains and these cells are found to serve as the initials of upper haustorium. The level of Chl b was lower than Chl a and xanthophylls in Cassytha when compared to Morinda. The photosynthetic activity was measured in intact leaves/stems of both the host and parasitic plant using Chl a fluorescence induction kinetics, which revealed that the photosynthetic efficiency was very low in the infected sample as well as in the parasite stem. Over all, the reduction in the photosynthetic efficiency was correlated to the poorly developed PS II complex

Effect of Crude Brassinosteroid Extract on Growth and Biochemical Changes of Gosssypium hirsutum L. and Vigna mungo L.

The present study was aimed to examine the influence of BRs on seed germination and seedling growth in Gossypium hirsutum L. Var Svpr 2 and Vigna mungo (L.) Hepper Var T9. The application of BRs on seed germination of Gossypium hirsutum increased the rate of germination considerably with varied percentage from 60.4 to 99. Vigna mungo seed also showed the varied percentage of germination from 56.8 to 80.1. Both the plants exhibited high percentage of vegetative growth such as shoot length, fresh weight, dry weight and leaf area on 3% of BR supplementation. The amount of chlorophyll a, b and total chlorophyll increased under BR treatments. Among the concentration, 3% BRs caused maximum effect than the other tested concentrations. High percentage of starch 53% and 31 % was observed in Gossypium and Vigna mungo respectively. The results of the present study shows that 3% BRs promotes the growth rate of Gossypium hirsutum L. Var Svpr 2 and Vigna mungo (L.) Hepper Var. T9. The results of the present study supplemented to the previous observations and practical utilization of the new steroidal group of phytohormones for large scale production of the economically important crops Gossypium hirsutum L. Var Svpr 2 and Vigna mungo (L.) Hepper Var. T9

Irradiance dependency of UV-a induced phase shifts in the locomotor activity rhythm of the field mouse mus booduga

In the nocturnal field mouse Mus booduga, the responsiveness of the circadian system to UV-A light of 2.5 W/m2 and 30 minutes duration is known to be phase dependent. The results of our experiments indicate that the phase shifts evoked by UV-A at the two phases, CT14 (circadian time 14) and CT20 increases nonlinearly with irradiance. (Chronobiology International, 17(6), 777–782, 2000