Evaluation of the physiological potential of Panicum maximum seeds by multivariate analysis

The aim of this work was to identify efficient vigor tests for differentiating the seed lots, forecasting seedling emergence in the field and assessing the physiological quality of Panicum maximum seeds. 12 seed lots from the cultivar Tanzania and 11 seed lots from the cultivar Massai were evaluated for water content, germination, first count and germination speed index, emergence and first emergence count of seedlings in sand, root length and shoot length, analysis of SVIS® images (seedling length, vigor and uniformity index) and seedling emergence in the field. The work was conducted in a completely randomized design for tests performed in the laboratory and in randomized blocks for tests in the field. The data were subjected to analysis of variance and the means compared by Scott Knott's test at 5% probability and statistical multivariate clustering analysis and principal components analysis. The shoot and root length tests are efficient for the evaluation of the physiological potential of P. maximum cv. Massai, while the seedling length, vigor index and growth uniformity index tests using image analysis, seedling emergence in sand and first seedling emergence count in sand are efficient in assessing the physiological potential of seeds of P. maximum cv. Tanzania, and providing information similar to that of seedling emergence in the field.

Avaliação do vigor de sementes de girassol por meio de análise de imagens de plântulas / Sunflower seed vigor evaluation by seedling image analyze

O trabalho teve como objetivo avaliar a eficiência do sistema computadorizado de análise de imagens de plântulas Seed Vigor Imaging System (SVIS(r)), em comparação com os outros testes recomendados para determinação do vigor de sementes de girassol. Foram utilizados dez lotes de sementes, cultivar Catissol 01, os quais foram avaliados quanto ao potencial fisiológico por meio dos testes de germinação, envelhecimento acelerado, emergência de plântulas em areia e em campo e análise de imagens de plântulas com o sistema SVIS(r), aos 0 e 4 meses de armazenamento. O delineamento experimental utilizado foi inteiramente casualizado para os testes realizados em laboratório e blocos ao acaso para o teste de emergência de plântulas em campo; em ambos os casos, foram utilizadas 4 repetições. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Scott Knott a 5% de probabilidade. Verificou-se que a análise computadorizada de imagens de plântulas com SVIS(r) é eficiente para avaliação do vigor de sementes de girassol.

This study aimed to evaluate the efficiency of computerized image analysis of seedling Seed Vigor Imaging System (SVIS(r)) compared with the other recommended tests to determine vigor in sunflower seeds. It was used ten seed lots of cultivar Catissol 01.The physiological potential was assessed using tests of germination, accelerated aging, seedling emergence and seedling image analyze with SVIS(r) at 0 and 4 months after storage. The experimental design was completely randomized for the laboratory tests and randomized blocs to seedling emergence on the field; in both cases it was used four replications. The data were submitted to variance analyze and mean comparisons at Scott Knott test (P<0,01). Seedling image analyze with SVIS(r) is efficient to access sunflower vigor seeds.