ABSTRACT
The study aimed to evaluate the influence of physiological seed quality on the spatial distribution of plants in the field, as well as the effect on variability among soybean plants. Six lots of soybean cultivar CD 202, with three vigor levels (high, medium and low) and two lots on each level were used. Lots of high physiological quality showed germination of 96% and lots considered of medium vigor showed 82% of germination and vigor between 60% and 67%, whereas lots of low vigor showed 70% germination and vigor between 55% and 58%. The test was conducted in plots formed by seven 5 m long rows with spacing of 0.45 m. The sowing was performed by opening furrows by hand with the equidistant distribution of seeds using marked rulers, corrected by the germination of each seed lot. Lots of seeds of higher vigor provide greater uniformity in the distribution of plants in the field. The reduction in seed physiological quality provides increased variability among plants within populations, throughout the entire developmental period of soybean, also affecting the seed yield per plant.
Subject(s)
Plants , Seeds , Glycine max , GerminationABSTRACT
The objective of this study was to evaluate the physiological and sanitary quality of seeds of rocket; the research was done at the Laboratory of Seed Analysis and greenhouse of the Department of Plant Science, Federal University of Pelotas (UFPel). Four lots of the cultivar "Antonella'' were tested for following features: initial and final moisture content, germination rate, first count of germination, accelerated aging with saline solution, dry matter contents, seedling shoot and root length, emergence speed index, emergence of seedlings in substrate, electrical conductivity and sanitary condition. A completely randomized design with four replications was used for all tests done and means were compared by Tukey test (P≤0.05). For all tests performed it was concluded that despite changes in the ranking of the best lots, there was agreement regarding the indication of the inferiority of the lot 3 in all tests and it was also observed that the incidence of fungi associated with seeds of rocket interfere with the physiological quality of the lots.
O objetivo nesta pesquisa foi avaliar a qualidade fisiológica e sanitária de sementes de rúcula. O trabalho foi conduzido no laboratório e em casa de vegetação do Departamento de Fitotecniada Universidade Federal de Pelotas (UFPel). No ensaio, foram utilizados quatro lotes de sementes de rúcula da cultivar 'Antonella', sendo efetuados os seguintes testes: grau de umidade inicial e após o envelhecimento acelerado, germinação, primeira contagem de germinação, envelhecimento acelerado com solução salina, massa seca da parte aérea e de raiz de plântulas, comprimento da parte aérea e de raízes de plântulas, índice de velocidade de emergência, emergência de plântulas, condutividade elétrica e teste de sanidade, em delineamento experimental inteiramente casualizado, com quatro repetições, sendo que as médias foram comparadas pelo teste de Tukey (P≤0,05). Apesar das alterações na classificação dos melhores lotes, nos testes analisados, verificou-se concordância quanto à indicação da inferioridade do lote 3 em todas as avaliações. Verificou-se que a incidência dos fungos associados às sementes de rúcula interfere na qualidade fisiológica dos lotes.
ABSTRACT
Muitos são os danos ocasionados por Colletotrichum gloeosporioides em plantas de cafeeiro, porém pouco são os conhecimentos sobre o estabelecimento do processo infectivo e sobre a evolução dos sintomas apresentados pelas plantas hospedeiras. Deste modo, o objetivo do estudo foi avaliar o comportamento de isolados de C. gloeosporioides obtidos de Cafeeiro em mudas produzidas a partir de sementes de plantas com sintomas de mancha manteigosa e sem sintomas de mancha manteigosa, estimar a agressividade do patógeno através da incidência e severidade da doença, comparando-os com um isolado oriundo de outra espécie vegetal. A partir da estimativa da incidência e severidade, observou-se que mudas oriundas de plantas com sintomas de mancha manteigosa são mais suscetíveis ao ataque de C. gloeosporioides. O isolado IS-II mostrou-se totalmente agressivo, apresentando um potencial crescente de doença em relação ao tempo.
Many are the damages caused by Colletotrichum gloeosporioides in coffee plants, but little is knowledge about the establishment of the infective process and the evolution of the symptoms presented by host plants. This study evaluated the behavior of isolates of C. gloeosporioides obtained from Coffee on seedlings grown from seeds with buttery spot symptoms and without symptoms of blister spot, estimate the aggressiveness of the pathogen through the incidence and severity of disease, comparing them with one isolate from other plant species. The estimation of the incidence and severity was observed that seedlings from plants with symptoms of blister spot are more susceptible to attack by C. gloeosporioides. The isolated IS-II shown to be fully aggressive, presenting a high potential for disease.