Wilt caused by Fusarium oxysporum f. sp. pisi is a serious production constraint for peas worldwide. An attempt was made to isolate wilt-resistant mutants in two susceptible pea genotypes, Arkel and Azad P-1, employing induced mutagenesis and in vitro selection techniques. Two thousand seeds of each genotype were mutagenized either with ethyl methane sulfonate (EMS, 0.2% and 0.3%) or gamma rays (5-22.5 kR) in 60 Co gamma cell for three consecutive years. Screening of different mutagenized populations under wilt-sick plots resulted in the isolation of 25 mutants exhibiting complete or enhanced wilt resistance compared to parental genotypes. Five of these wilt-resistant mutants also outperformed the susceptible background genotypes in terms of yield and other horticultural traits. Efforts were also made to isolate wilt-resistant regenerants from callus cultures exhibiting insensitivity to culture filtrate (CF) of F. oxysporum f. sp. pisi. A total of 250 regenerants (R 0 ) were obtained from CF-insensitive calli selected from medium supplemented with 20% culture filtrate. When evaluated in artificially inoculated sick plots, only five R 2 lines obtained from the regenerants exhibited enhanced wilt resistance compared to parental cultivars. However, the selected lines did not exhibit resistance levels equivalent to those shown by wilt-resistant lines isolated through in vivo mutagenesis. To conclude, induced mutagenesis through irradiation and EMS treatments exhibited superiority over in vitro selection for inducing wilt resistance in peas.

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Earlier researchers like Turkeli, suggested that 'the factors which determine the productivity of scientists are admittedly complex and perhaps not amenable to real scientific analysis'. The present investigation was designed with the sole purpose of confronting such a complex problem. Nearly 200 variables influencing research productivity were collected through relevant literature, analysis of biographies of great scientists, and discussion with eminent scientists. Finally, through a critical examination, 80 variables were selected for the use of Q-sort technique. The sample for the study consisted of a cross section of scientists ranging from Fellows of Indian National Science Academy to young agricultural scientists. Mailed questionnaires and personal interview methods were used for collecting data. Out of a total of 912 respondents, reply was obtained from 325. On the basis of Q-sorted data, 26 variables were selected for further analysis and they were subjected to principal component factor analysis.. The results indicated eleven factors affecting research productivity of scientists. They were: persistence, resource adequacy, access to literature, initiative, intelligence, creativity, learning capability, stimulative leadership, concern for advancement, external orientation, and professional commitment.A. RAMESH BABU, Y.P. SINGH: DETERMINANTS OF RESEARCH PRODUCTIVITY reporting on her eminent scientists Roe 3 remarked that the one characteristic all of them seemed to have had without exception is an intense devotion to their work. Crane 4 emphasized that at any stage of the career cycle, scientists at universities high in prestige are more likely to be productive and win recognition than scientists at universities low in prestige. Singh and Laharia 5 concluded that an intimate association exists between inter-personal communication and scientific productivity. Zamaripa 6 attempted to determine which measures should be used in assessing research productivity? The most important measures were: the number of publications in refereed journals, the number of grants awarded to the unit each year, and the number of papers presented at national scientific meetings. Design and data analysisIn order to study the research productivity of scientists, nearly 200 variables were collected through an extensive search of relevant literature, critical analysis of biographies of great scientists 7 and thorough discussion with eminent scientists. The variables were grouped broadly under personal and organizational variables.The 200 variables were critically examined with a view to detect ambiguity and repetitiveness. Finally 80 variables were selected for the use of Q-sort technique. 8 Printed cards of size 3 1/2"• numbering 80 containing items and code numbers, along with instruction sheet and rank sheet 9 were mailed to the following five categories of scientists. Fellows of Indian National Science Academy (FNAs), eminent agricultural scientists, agricultural research managers, award winners of the Indian Council of Agricultur...

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The potential for improvement in crops is proportional to the magnitude of genetic variability present in the germplasm. Thirty genotypes of chilli pepper (Capsicum annuum L.) were evaluated during the summer rainy seasons of 2005 and 2006 to study the extent of genetic variability, determine the association between different characters, understand direct and indirect effects of component traits on fresh and dry yield, and identify desirable genotypes. The project was undertaken at the experimental farm of the Department of Vegetable Science and Floriculture, CSK HPKV, Palampur, India. Sufficient variability was observed for all horticultural and quality traits studied; that is, days to 50% flowering, days to first harvest, primary structural branches per plant, secondary branches per plant, fruit length, fruit diameter, average fruit weight, number of seeds per fruit, 100-seed weight, pericarp:seed ratio, number of marketable fruits per plant, number of total fruits per plant, plant height, marketable yield per plant, total soluble solids, and oleoresin, capsanthin, and capsaicin content. On the basis of mean performance, the genotype Palam Yellow was found to be promising for marketable fresh yield; on the basis of dry yield, the genotype Surajmukhi was found to be promising. High phenotypic (PCV) and genotypic coefficients of variation (GCV) were observed for marketable fresh and dry yield per plant, numbers of marketable fruit, average fresh and dry fruit weight, fruit length and diameter, seed weight per fruit, number of primary structural branches per plant, and oleoresin and capsaicin content. Moderate PCV and GCV were recorded for numbers of secondary branches per plant, plant height, harvest duration, number of seeds per fruit, 100-seed weight, pericarp:seed ratio, ascorbic acid, and capsanthin. High heritability coupled with high genetic advance was noted for marketable fresh and dry yield per plant, average fruit weight, numbers of marketable fruit, fruit diameter, and oleoresin and capsaicin content, which indicated the role of additive gene action for the inheritance of these traits. These traits are likely to respond better to selection. Correlation and path analysis studies indicated that average fruit weight, numbers of total and marketable Address correspondence to Yudhvir Singh, Improvement in Chilli Peppers 341 fruits per plant, and fruit length contributed to marketable fresh yield. Average dry fruit weight, numbers of total and marketable fruits per plant, seed weight per fruit, and harvest duration played a predominant role for predicting dry yield. Among quality traits, capsanthin was significantly and positively correlated with yield. Ascorbic acid and capsaicin content were positively associated with total soluble solids at green and red stage, respectively.