Influence of Seed Pelleting on Physiological Seed Quality Improvement in Bael (Aegle marmelos (L.) Corr.) the Endangered Medicinal Tree

Aim: Bael is an endangered medicinal tree with multipurpose utility propagated through seeds. Hence attempts were to improve the vigour of the seed through seed pelleting with ecofriently organic products. Study Design: A Factorial completely randomized design (FCRD) for laboratory experiments and RBD for nursery studies with five replication with five replications. Place and Duration of Study: The laboratory and nursery experiment was conducted at the Department of Seed Science and Technology, Tamil Nadu Agricultural University, Coimbatore during 2012-13. Methodology: The seeds were pelleted with botanical leaf powders viz., karisilanganni (Eclipta prostrate), avaram (Cassia auriculata), arappu (Albizia amara), neem (Azadirachta indica), biofertilizers viz., azophos, phosphobacteria and biocontrol agents viz., Trichoderma viride and Pseudomonas fluorescens along with unpelleted seeds. Results: The results showed that among the treatments arappu pelleting enhanced the germination (76%) and seedling quality characters viz., root length (13.0 cm), shoot length (9.9 cm), dry matter production (318 mg) and vigour index (1740) compared to control followed by neem and phosphobacteria pelleting. The treatment scored as best also performed better at polypot nursery. Conclusion: Our data show that arappu pelleting enhanced seed quality compared to control

In vitro evaluation of aqueous seed extract of Psoralea corylifolia L. on seed germination and seedling vigour of maize.

Aqueous seed extract of seeds of P.corylifolia were evaluated for seed germination and vigour index at 10, 20, 30, 40 and 50% concentration for 3,6, 12 and 24hours of treatment in maize seeds. Maximum and significant activity was observed in 20% concentration at 12hours of duration and recorded 88.0% germination and 1398.5 vogour index. Compared to control, it was recorded 72.1% germination and 1010.1 vigour index. In 30 and 40% concentration at 12 hours of duration, significant activity was recorded. In 6 hours of duration, moderate activity was observed in 10, 20, 30 and 40% concentration. No significant activity was observed in 3 hours and 24 hours duration at 10, 20, 30, 40 and 50% concentration of aqueous seed extract.

Differential toxicity of cadmium to mustard (Brassica juncia L.) genotypes under higher metal levels.

Cadmium application inhibited various growth and biochemical parameters in seedlings of five cultivars of Brassica juncia L. with different magnitude at lower Cd supply, however, at higher metal applications the variation in Cd toxicity ranged with minor differences. The seedling vigour index (SVI) was inhibited more severely in Gangotri (62.25% over control) and least in Pusa Jai Kisan (8.95%) at 1.0 mM CdCl2. The SVI of all five mustard cultivars, however, severely inhibited (84.29-91.80%) at 5.0 mM Cd. The root and shoot elongation in 7 days old seedlings were inhibited by 32.39-40.38 and 11.83-56.40% respectively at 1.0 mM CdCl2, whereas the varietal differences in root and shoot elongation were 76.71-82.47 and 71.57-78.91 respectively at 5.0 mM CdCl2. The genotypic differences at lower Cd level were more pronounced in shoot elongation than that in the root elongation. The dry weight and moisture content of the seedlings, however, does not show much varietal differences even at lower Cd level, though the Cd toxicity increased at higher level of Cd application. The metal tolerance index (MTI) and % phytotoxicity of 3 days old seedlings ranged between 43.30-98.37 and 1.63-56.70% respectively at 1.0 mM CdCl2 for different mustard genotypes, whereas at 5.0 mM CdCl2 these factors ranged between 12.26- 20.92 and 80.08-87.74% respectively. The varietal differences of MTI and % phytotoxicity was, however, less pronounced at all the metal levels when the seedling attained an age of 7 days. A similar trend of genotypic variation was noticed in Cd accumulation in the seedlings at lower and higher levels of Cd supply to the seedlings. Amongst some biochemical parameters e.g. photosynthetic pigments, carbohydrates and proteins in the leaves, the photosynthetic pigments i.e. chlorophylls and carotenoids were decreased more drastically. The carbohydrate content of leaves, however, was the least affected component. Our data indicate that the differential toxicity of cadmium to Indian mustard genotypes was dependent on the level of contamination and growth phases.

Superação da dormência e avaliação da qualidade fisiológica de sementes de Sesbania virgata / Dormancy break and evaluation of physiological quality of Sesbania virgata seeds

A avaliação da qualidade fisiológica de lotes de sementes de Sesbania virgata é dificultada pela dormência inerente à espécie, bem como pela inadequação metodológica de testes disponíveis. Para desenvolver procedimentos adequados à avaliação da qualidade das sementes de S. virgata, foram avaliados métodos tanto para quebra de dormência como para realização do teste de tetrazólio. Em uma primeira fase, as sementes de cinco lotes foram submetidas a tratamentos para quebra de dormência: lixa, ácido e corte do tegumento, previamente ao teste de germinação. Para caracterização dos lotes e adequação da metodologia do teste de tetrazólio, na segunda fase, as sementes foram lixadas na região oposta ao eixo embrionário, e submetidas aos seguintes testes: tetrazólio, germinação, velocidade de emergência, peso de matéria fresca e de matéria seca de plântulas. Foram utilizados dois métodos de pré-condicionamento: embebição em papel por 18 h a 30 ºC e imersão em água por 12 h a 30 ºC e três períodos (uma, duas e três horas) de imersão em solução de tetrazólio 0,5%. Na análise do perfil dos lotes de S. virgata foram detectadas variações na qualidade fisiológica pelos resultados dos testes de vigor e germinação. O método de escarificação com lixa possibilitou a quebra de dormência das sementes de S. virgata,e o pré-condicionamento das sementes em papel com embebição em solução de tetrazólio 0,5% por duas horas é um procedimento adequado para avaliação da viabilidade das sementes.

The evaluation of Sesbania virgata seed physiological quality is hampered by its intrinsic seed dormancy and inadequate methodologies among available tests. To develop an adequate procedure to evaluate S. virgata seed quality, methods for dormancy breaking and tetrazolium test accomplishment were evaluated. In a first stage, seeds from five lots were submitted to dormancy breaking methods: sandpaper, acid and tegument cuts, followed by germination tests. To characterize lots and adapt a tetrazolium-test, in a second stage, seeds were sanded in the area opposite to the embryonic axis and submitted to the following tests: tetrazolium, germination, vigor index, fresh and dry weight. Two preconditioning conditions (soaked paper for 18 h at 30 ºC and immersion in water for 12 h at 30 ºC) and three immersion timespan (one, two and three hours) in tetrazolium solution 0.5% were used. In the S. virgata lot profile analysis, variations were detected in its physiological quality according to vigor index and germination results. Scarification method with sandpaper better broke S. virgata seed dormancy, and preconditioning seeds in soaked paper followed by immersion in tetrazolium solution for two hours was the appropriate procedure to assess seed viability.