Interconversion of stereoisomers of endosulfan on chickpea crop under field conditions

The pure individual stereoisomers of endosulfan, alpha-endosulfan and beta-endosulfan, were applied as emulsifiable concentrates to chickpea crop at the rate of 175 g a.i. ha −1 and 50 g a.i. ha −1, respectively. The dissipation rate of these isomers revealed that alpha-endosulfan interconverted to beta-endosulfan in minor quantities, while it was converted into endosulfan sulfate on chickpea leaves in significant amounts. On application, beta-endosulfan was converted to endosulfan sulfate and alpha-endosulfan in relatively smaller amounts. The study indicates that the beta stereoisomer of endosulfan is more persistent because it is resistant to interconversion and metabolic change.     

Sequence and evolutionary analysis of ribosomal DNA from Huanglongbing (HLB) isolates of Western India

Citrus greening (Huanglongbing, HLB) is a widespread and economically important citrus disease all over the world. The disease is caused by a phloem-limited fastidious gram negative bacterium, “Candidatus Liberibacter spp.” which belongs to the alpha-proteobacteria group classified on the basis of its 16SrDNA sequence. Although the pathogen has been classified under three distinct groups, viz. Asian, African and American isolates, nothing is known about the status and the molecular variabilities among the Indian HLB isolates collected from different citrus cultivars grown in India. Five different HLB isolates showing variable symptoms based on their severity of infection on different citrus, viz. Mosambi, Rangpur lime, Cleopatra mandarin, acid lime and rough lemon, were studied by PCR amplification, sequence and evolutionary analysis of their 16S and 16S/23S rDNA intergenic regions. Analysis of the 16S/23S rDNA intergenic region separated all five Indian isolates from existing African isolates but failed to differentiate among Asian, American and Indian isolates. However, further analysis of complete 16S rDNA clearly indicated that Indian isolates fall within the Asian HLB group. Overall, our results suggest that all the five Indian HLB isolates taken for the current analysis belong to the Candidatus Liberibacter asiaticus strain, which showed distinct sequence variabilities and produced noticeable symptoms on the citrus trees. These results provide a robust framework for understanding how differences in pathogenicity among various HLB isolates may be related to evolutionary history.     

Flufenoxuron, an acylurea insect growth regulator, alters development of Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) by modulating levels of chitin, soluble protein content, and HSP70 and p34 in the larval tissues

The effect of sublethal concentrations, 0.00141% (LC₂₀), 0.00251% (LC₃₀), and 0.0036% (LC₄₀) of a dispersible formulation of an acylurea insect growth regulator, flufenoxuron (Cascade) on certain biochemical parameters in the larvae of Tribolium castaneum was investigated. When neonates were fed on diet treated with sublethal concentrations for 24 h, it was observed that at all concentrations tested, there was a significant reduction in chitin content on the 15th day of development. Total soluble protein content at LC₂₀ and LC₃₀ decreased with increasing age of the larvae. At LC₂₀ and LC₄₀ concentrations there was a progressive increase in the protein: chitin ratio as a function of increase in age of the larvae. SDS-PAGE analysis of the larval tissue extracts indicated gross quantitative changes in some of the protein bands (MW 50-97 kDa). Western blot analysis revealed significant increase in the level of HSP70 in the extracts of larvae fed on LC₃₀ treated diet, on the 7th and 10th day of development in the decreasing order. Conversely, a significant decrease in the hyper-phosphorylated form of p34^cdc2 kinase due to flufenoxuron treatment indicating modulation of cell cycle regulation was observed. Thus, sublethal concentrations of flufenoxuron alter expression of developmentally regulated proteins, HSP70 and p34^cdc2 and chitin formation in a stage-specific manner thereby resulting developmental abnormalities in T. castaneum.     

Adapting clonally propagated crops to climatic changes: a global approach for taro (<Emphasis Type="Italic">Colocasia esculenta</Emphasis> (L.) Schott)

Clonally propagated crop species are less adaptable to environmental changes than those propagating sexually. DNA studies have shown that in all countries where taro (Colocasia esculenta (L.) Schott) has been introduced clonally its genetic base is narrow. As genetic variation is the most important source of adaptive potential, it appears interesting to attempt to increase genetic and phenotypic diversity to strengthen smallholders’ capacity to adapt to climatic changes. A global experiment, involving 14 countries from America, Africa, Asia and the Pacific was conducted to test this approach. Every country received a set of 50 indexed genotypes in vitro assembling significant genetic diversity. After on-station agronomic evaluation trials, the best genotypes were distributed to farmers for participatory on-farm evaluation. Results indicated that hybrids tolerant to taro leaf blight (TLB, Phytophthora colocasiae Raciborski), developed by Hawaii, Papua New Guinea and Samoa breeding programmes outperformed local cultivars in most locations. However, several elite cultivars from SE Asia, also tolerant to TLB, outperformed improved hybrids in four countries and in one country none of the introductions performed better than the local cultivars. Introduced genotypes were successfully crossed (controlled crossing) with local cultivars and new hybrids were produced. For the first time in the history of Aroids research, seeds were exchanged internationally injecting tremendous allelic diversity in different countries. If climatic changes are going to cause the problems envisaged, then breeding crops with wide genetic diversity appears to be an appropriate approach to overcome the disasters that will otherwise ensue.     

Present position regarding breeding of mango (Mangifera indica L.) in India

Summary Progress of hybridization work at various centres in India is reviewed. With the improved technique of mango hybridization and the report of self-incompatibility in mango, it will be possible to evolve a larger number of hybrids for screening for desirable characters. Embryological studies have shown that in mango pollen tubes grow down the style and effect fertilization but the development of zygote is blocked leading to a sporophytic type of self-incompatibility. Hybrids recently evolved through the combinations of regular and commercial biennial bearing varieties indicate that largescale hybridization may offer a solution to the biennial bearing problem in mango.Paper read at the International Horticultural Congress, Maryland, Maryland, U.S.A., 1966.     

Antibacterial spectrum of Hypericum hookerianum.

The antibacterial activity of the chloroform, acetone and methanol extracts of Hypericum hookerianum leaves and stems was evaluated. All extracts showed antibacterial activity against six different gram-positive and gram-negative bacteria, the methanol extracts exhibiting the maximum inhibitory activity at 400 microg/ml.     

The influence of wax emulsion,morphactin and gibberellic acid on the storage behaviour of indian gooseberry fruits

Qualities of Indian gooseberry fruits (Phyllanthus emblica L.) were determined after dip-treatment with wax emulsion (WE) with or without morphactin (Mor) and gibberellic acid (GA₃). Dip-treatments with 100–500 mg l^?1 Mor reduced marketability by inducing browning and high weight loss, but loss in ascorbic acid was checked and phenols increased. 10 mg l^?1 Mor maintained marketability at par with control, effectively controlled loss in ascorbic acid, and increased acidity and reducing sugars. GA₃, although failing to control the loss of ascorbic acid, was effective in checking browning and thereby increased the market value of fruits as compared with controls and Mor-treated fruits.WE with or without Mor (10 mg l^?1) controlled browning, accumulation of phenols and losses in weight and moisture as compared with 10 mg l^?1 Mor, 100 mg l^?1 GA₃, or control, but could not retain ascorbic acid in comparison to 10 mg l^?1 Mor-treated fruits. Marketability of fruits having had treatment with either WE or GA₃ was the same. Fruits having had combined treatment with WE and 10 mg l^?1 Mor had maximum marketability. Minimum marketability was observed in fruits subjected to a combined treatment of WE + 100 mg l^?1 GA₃ due to maximum infection with Aspergillus spp. and Penicillium spp.     

Polymorphism of BMPR1B,BMP15 and GDF9 fecundity genes in prolific Garole sheep

Tropical Animal Health and Production - Mutation studies in different prolific sheep breeds have shown that the transforming growth factor beta super family ligands viz. the growth differentiation...     

Effect of supplementation of vitamin E,copper and zinc on the in vitro phagocytic activity and lymphocyte proliferation index of peripartum Sahiwal (Bos indicus) cows

To study the effect of vitamin E (VE), copper (Cu) and zinc (Zn) supplementation on the in vitro phagocytic activity (PA) and lymphocyte proliferation response (LPR) of blood neutrophils and lymphocytes, thirty Sahiwal pregnant cows (six in each group) in their late gestation at 30 days before the expected date of calving were selected from the NDRI experimental herd and supplemented with various micronutrients from 30 days before calving to 45 days after calving. Cows were supplemented individually with VE (1000 IU/cow/day), Cu (20 ppm/cow/day) and Zn (80 ppm/cow/day) and also with a combination of VE, Cu and Zn to study cumulative effect of all micronutrients. One group without any supplementation acted as a control. Blood neutrophils and lymphocytes were isolated and studied for their PA and LPR. Supplementation of micronutrients like VE, Cu, Zn and a combination of all these nutrients significantly (p < 0.01) increased the PA of experimental cows as compared to control (unsupplemented) cows during the pre‐partum period. During post‐partum, all the micronutrients (VE, Cu, Zn and their combination) showed a significant (p < 0.01) increase in the PA of experimental cows as compared to control cows. Of all the groups, significant (p < 0.01) and maximum PA was observed in the combination group followed by Zn‐supplemented group during both the pre‐ and post‐partum period. A significant (p < 0.01) increase in LPR of B lymphocytes was observed in combination‐supplemented group during the pre‐partum period and during both the pre‐ and post‐partum period in the Cu‐supplemented group.     

Standardization of Rootstocks of Mango (Mangifera Indica L.)

Mango cuttings could be induced to form roots provided IBA at 5,000 p.p.m. in lanolin was applied at the base of shoots after removing a ring of bark while they were still attached to the mother tree.

Cuttings taken from one-month-old seedlings gave the highest percentage of rooting and establishment, but with increasing age of the mother plants the rooting was considerably reduced. The rooting of cuttings of different age groups could be improved by using shoots forced into vigorous growth by hard pruning. Younger plants responded better to such treatment than older ones.

Cuttings from etiolated shoots rooted better than those from non-etiolated, but etiolation was less effective in promoting rooting than invigoration by hard pruning. Etiolation and invigoration combined gave the highest percentage of rooting and establishment in all age groups.