Sowing

About: Sowing is a research topic. Over the lifetime, 33888 publications have been published within this topic receiving 273438 citations. The topic is also known as: seeding.

Biopriming of sunflower (Helianthus annuus L.) seed with Pseudomonas fluorescens for improvement of seed invigoration and seedling growth

Abstract: Biopriming treatment is potentially able to promote rapid and more uniform seed germination and plants growth associated with bacterial coatings. In this study, we report application of some effective biological agents on sunflower seed and their impact on seedling. We investigated the effects of 30 strains of Pseudomonas fluorescens on improving sunflower seed germination and promotion of seedling growth. After selection of efficient strains, efficacy of biopriming seed treatment was compared with seed inoculation and priming treatments. Two strains, including UTPf76 and UTPf86, were selected for next experiments because they enhanced seed factors such as germination index, germination percentage, germination rate and vigor index and also seedling growth indices including root length, shoot height, dry and wet weight of seedlings and numbers of lateral roots. In biopriming, the selected strains were applied to the seed during osmopriming with NaCl. Biopriming was significantly improved by the capability of these strains and the highest amount (P= 0.01) of shoot height (28.2 cm), root length (35.9 cm) and seedling weight (8.9gr) reached, in comparison with other treatments and the control. As a conclusion, biopriming with Pseudomonas fluorescens UTPf76 and UTPf86 have provided very well establishment and adherence of bacteria to the seed, before planting, and thus is suggested as a proper treatment for enhancement of seed indices and improvement of seedling growth.

Size and composition of the weed seedbank under different management systems for continuous maize cropping.

Abstract: The size and composition of the weed seedbank after 5 years of maize (Zea mays L.) continuous cropping under four crop management systems was evaluated. The management systems included a conventional system (ploughing, full-rate fertilization, broadcast pre-emergence herbicides), an organic system (ploughing, organic fertilization, physical weed control), a reduced-input system (rotary harrowing, low-rate fertilization, physical post-emergence herbicides) and a strip-cultivation system (non-tillage, banded fertilization and herbicides at sowing, broadcast top-dress fertilization and post-emergence herbicides). Seedbank sampling was performed after maize harvest by taking 270 soil cores per management system at depths of 0-10, 10-20 and 20-30 cm. Weed seedbank size was largest under the organic system (100 761 seeds m -2 ) and smallest under the conventional system (27 601 seeds m -2 ). Differences among maize management systems depended mainly upon weed control efficacy rather than upon tillage effects. Four of the eight major weed species showed differential responses to tillage and weed control methods carried out within maize management systems. Canonical discriminant analysis showed that maize management systems based upon reduced tillage had more characteristic weeds than systems based upon ploughing. Amaranthus retroflexus L., Chenopodium album L., Digitaria sanguinalis L. and Solanum nigrum L. were the most troublesome weeds for the cropping system under study; their relative importance in the seedbank usually varied according to maize management system.