Case of leucism in the spadenose shark, Scoliodon laticaudus (Müller and Henle, 1838) from Mangalore, Karnataka

The present paper reports the first case of leucism in the spadenose shark, Scoliodon laticaudus from India. This report is based on the study of a single specimen of S. laticaudus caught by a commercial trawler off Mangalore coast. Photographs were taken and measurements recorded using vernier calipers. Partial reduction in pigmentation and no other morphometric differences were seen between the specimen studied and other normal spadenose sharks. Conclusion of leucism in the specimen was done based on the partial lack of integumentary pigments and normal eye colour

Screening Sunflower for Tolerance to Sunflower Midge Using the Synthetic Auxin 2,4-Dichlorophenoxyacetic Acid

The sunflower midge, Contarinia schulzi Gagné, causes economic damage by inducing abnormal growth in infested heads (capitula) of sunflower, Helianthus annuus L. The primary objective of this study was to determine whether sunflower midge damage could be simulated and whether that simulated damage could be used to select midge-tolerant sunflower germplasm. An additional objective was to develop a quantitative alternative to the scoring systems used to visually estimate damage. Sunflower plants were treated by injecting buds with the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D), which resulted in a distortion of the head morphology that was similar in appearance to the damage caused by the sunflower midge. The extent of distortion depended not only on the dose of 2,4-D but also on the size and growth stage of the head when injected. Among sunflower hybrids tested, resistance to the sunflower midge was significantly, negatively correlated with 2,4-D damage. Therefore, injection of sunflower heads with 2,4-D appears to be an effective method of screening sunflower germplasm for tolerance to the sunflower midge. Two distortion indices, based on measurements of head shape, were compared with the visual damage system. Although the visual rating system is faster, distortion index 2 gave similar results and is preferred when it is necessary to avoid individual differences in scoring techniques

Screening Sunflower for Tolerance to Sunflower Midge Using the Synthetic Auxin 2,4-Dichlorophenoxyacetic Acid

The sunflower midge, Contarinia schulzi Gagné, causes economic damage by inducing abnormal growth in infested heads (capitula) of sunflower, Helianthus annuus L. The primary objective of this study was to determine whether sunflower midge damage could be simulated and whether that simulated damage could be used to select midge-tolerant sunflower germplasm. An additional objective was to develop a quantitative alternative to the scoring systems used to visually estimate damage. Sunflower plants were treated by injecting buds with the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D), which resulted in a distortion of the head morphology that was similar in appearance to the damage caused by the sunflower midge. The extent of distortion depended not only on the dose of 2,4-D but also on the size and growth stage of the head when injected. Among sunflower hybrids tested, resistance to the sunflower midge was significantly, negatively correlated with 2,4-D damage. Therefore, injection of sunflower heads with 2,4-D appears to be an effective method of screening sunflower germplasm for tolerance to the sunflower midge. Two distortion indices, based on measurements of head shape, were compared with the visual damage system. Although the visual rating system is faster, distortion index 2 gave similar results and is preferred when it is necessary to avoid individual differences in scoring techniques

Marine catfish resources of India

The marine catfish production showed a continuously declining trend all along the Indian Coast, from 67,666 t (1982) to 37,518 t (1995), while the situation is alarming along the SW and SE coast. This group is one of the most vulnerable resources for irrational harvest during their migratory and breeding phase. With the advent of mass harvesting gear like purse seine and trawlers, there has been a continuous onslaught on this resource during the periods of south bound or north bound migrations parallel to the coast. The damage is further aggravated when their spawning shoals are exploited from the surface often causing large scale destruction of parents and egg / embryos, leading to overfishing affecting the recruitment to the population. The paper gives the possible migratory route, seasons of vulnerability and impact of fishing gear on the resources. It is attempted to corelate the surface drift with the seasonal migrations. Various management practices are proposed to conserve the threatened species and suggested possible lines of exploitation preferably on the non-migratory species from distant waters in the middle shelf

Revival of fishery of the thinspine sea catfish, Arius tenuispinis at Mumbai, Maharashtra

Catfish landings by trawlers in Mumbai comprise of three major species viz., Arius dussumieri, Osteogeneiosus militaris and Arius caelatus with A. dussumeri, forming approximately 30-35% of the landings. However, of late the landings of Arius tenuispinis has showed an unusual upward trend at New Ferry Wharf, Mumbai and the species is observed in the catch almost throughout the year. Analysis of A. tenuispinis catch data from New Ferry Wharf during the period 1987 to 2012 clearly indicates collapse of the fishery of this species, showing signs of subsequent revival

Catfish resource in the Indian shelf waters

At attempt is made to analyse the bottom trawl fishing data collected by 91 cmises of FORV Sagar Sampada (1985 - '91). The vessel trawled in 544 stations spread over both the coasts up to a depth of 100 m and catfishes appeared in 54 stations with catch 3 -2401 kg/hr. The dominant species occurred beyond 50 m depth belt was invariably Tachysurus thalassinus whereas shoaling species like T. tenuispinis and T.dussumieri are reported from grounds less than 50 m. The resource has better abundance in 51 -100 m depth belt along northwest and northeast region

Evaluation of improved pigeon pea (Cajanus cajan) varieties for organoleptic dal quality in India

Pigeon pea (Cajanus cajanL.) is an important pulse crop in the Indian diet and one of the most important sources of dietary protein for the population. Organoleptic qualities of pigeon pea dal were tested to draw conclusions on the preferred varieties. Organoleptic qualities such as taste, texture, aroma, tenderness, sweetness and overall acceptance were tested by a trained sensory panel. Available and commercially viable improved varieties were selected for the analysis. All samples were milled and cooked under the same conditions. Results indicated that PUSA ARHAR 16, one of the improved varieties, presents a good potential in terms of agronomic characteristics for farmers and is also well accepted by the sensory panel during the organoleptic evaluation. Generating sound scientific evidence on organoleptic characteristics of pigeon pea is important for the breeders, as they will evaluate which varieties have a commercial potential and are accepted by the consumers

Present status of exploitation of fish and shellfish resources: Catfishes

The availability, abundance and yield of catfishes are very much influenced by the monsoon along the west coast of India. More than 55% of the annual total catfish production from the west coast (1984-'88) is realised during postmonsoon period and 35.6% in premonsoon and 9.2% in monsoon. The gear wise and season wise catfish production, abundance and species composition in different States and at selected fishing centres on the west coast are presented. Catfish resource has high abundance during monsoon at Veraval, Bombay, Calicut and Cochin. Although the yield is low during the monsoon period, it is proportionate to the effort put in at all the centres. All along the west coast, Tachysurus dussumieri (32.4%) is the most dominant species in the fishery of premonsoon period and T. thassinus (42.4%) in that of monsoon. The percentage contribution of T. tenuispinis and T. dussumieri during postmonsoon is about 28