Size, physiological quality, and green seed occurrence influenced by seeding rate in soybeans

Abstract

The seeding rate influences the intraspecific competition, which might affect the development and quality of seeds in soybean. However, the impact of seeding rate on the physical and physiological qualities of soybean seeds needs to be better elucidated. This study aimed to evaluate the effects of soybean plant density on the seed size as well as the effects of the interaction between the plant density and seed size on the seed mass, green seed occurence, and physiological seed quality. The experiments were carried out in the growing seasons of the years 2013/14 and 2014/15 in a Latossolo Vermelho distroférrico, under a randomized complete block design, using the NK 7059 RR cultivar with six replications. Four plant densities (150, 300, 440, and 560 thousand viable seeds ha -1 ) were evaluated. After the classification of seeds into four sizes, using a set of sieves, a 4 ×4 factorial scheme was used for the statistical analysis of the four plant densities and four seed sizes. The seed samples were evaluated for the seed mass, green seed percentage, germination, and vigor. Under thermal and water stress during seed development, an increase in the seeding rate led to a reduction in the green seed occurrence and an increase in the seed size and mass. However, in the absence of thermal and water stress, the seed size and mass were not altered by the seeding rate and, there was no occurrence of green seeds. Key words: Plant density. Chlorophyll retention. Green seeds. Seed vigor. ResumoA densidade de semeadura, por influenciar na competição intraespecífica, pode afetar o desenvolvimento e a qualidade das sementes de soja produzidas. Entretanto, o impacto da densidade de semeadura sobre a qualidade física e fisiológica das sementes de soja precisa ser melhor elucidado. Objetivou-se avaliar os efeitos da densidade de semeadura sobre o tamanho das sementes produzidas e a interação entre a densidade de semeadura e o tamanho das sementes sobre a massa, a ocorrência de sementes verdes e a qualidade fisiológica das mesmas. O experimento foi conduzido nas safras 2013/14 e 2014/15, em um Latossolo Vermelho distroférrico, sob o delineamento de blocos casualizados, utilizando-se a cultivar NK7059 RR, com seis repetições. Os tratamentos consistiram de quatro densidades de semeadura (150, 300, 440 e 560 mil sementes viáveis ha -1 ). Após a classificação em peneiras das sementes produzidas, adotou-se o esquema fatorial 4 x 4, com 4 densidades e 4 tamanhos de sementes. Avaliaram-se a massa de mil sementes, porcentagem de sementes verdes, germinação e vigor. O aumento na densidade de

Plant spatial arrangement affects grain production from branches and stem of soybean cultivars

“…plant densities probably enhanced the efficiency of soil water exploration in depth and, on the other hand, the water consumption was little affected by this variable, as discussed by Ferreira et al (2017), improving the water supply for plants grown at higher densities, culminating in a greater M1000 of both stem and branches. In both growing seasons the row spacing influenced total grain production per plant (Tables 1 and 3).…”

Вплив Біопрепаратів Комплексної Дії На Посівні Якості Насіння Сої

“…Якісне насіння формується у певних умовах навколишнього середовища [11][12][13][14][15]. Сівба якісним насінням сприяє ефективній реалізації генетичного потенціалу врожайності сучасних сортів сої [16][17][18].…”

Potencial fisiológico de sementes de diferentes estratos da planta de soja em densidades reduzidas

“…Seed formation depends on the supply of photoassimilates, and this can be influenced by the number of pods as well as the position of the pods on the plant (Huber et al, 2016). Therefore, reducing SR can affect the partition of photoassimilates by altering architecture and morphology (Gaspar & Conley, 2015), and these changes can alter the size and quality of the seeds produced (Baron et al, 2018;Ferreira et al, 2017;Werner et al, 2017). However, growing soybeans at a recommended SR can result in an excessive leaf area index, especially in years of high rainfall and conditions favorable to vegetative growth.…”