PRIMING AND GROWTH INHIBITOR IN THE PRODUCTION OF HIGH-QUALITY PEPPER SEEDLINGS

This study aimed to evaluate the effect of nitrate salts and a growth regulator on seed conditioning. Subsequently, the responses of the influence of the leaf application of paclobutrazol (PBZ) and nitrogen on the quality of seedlings of Capsicum frutescens L. were evaluated. Two experiments were carried out. The first experiment was conducted in a completely randomized design to evaluate priming, as follows: T1 – control, T2 – control (water), T3 – 0.2% calcium nitrate, T4 – 0.2% potassium nitrate, T5 – 0.1% calcium nitrate + 0.1% potassium nitrate, T6 – PBZ, and T7 – PBZ + 0.1% calcium nitrate + 0.1% potassium nitrate. The second experiment was carried out in a completely randomized design in a 2×5 factorial scheme consisting of priming (absence and presence of calcium nitrate) and leaf application of growth regulator, as follows: control (water), PBZ, PBZ + 1% nitrogen (calcium nitrate), PBZ + 1% nitrogen (urea), and PBZ + nitrogen (0.5% calcium nitrate + 0.5% urea). Physiological conditioning with a solution of 0.1% calcium nitrate increased the germination and seedling emergence rate and resulted in seedlings with a higher shoot length at 33 days after sowing (DAS), but seedlings at 50 DAS showed no differences in growth with its use. Leaf application of 0.1% paclobutrazol provided pepper (C. frutescens L.) seedlings with better distribution in growth according to the Dickson quality index.

OBTAINING “ORGANIC SEEDS” OF VEGETABLE AND INDUSTRIAL PLANTS USING THE AERODYNAMIC PROPERTIES OF THE SEEDS

The production and quality of any agricultural crop is determined both by the factors acting from the moment of sowing until harvesting, as well as by those that directly influence the seeds before sowing. In the organic cultivation of cereals, industrial plants, vegetables, medicinal plants, the seeds must be clean without any impurities because the maintenance of these crops does not allow using chemicals. There is a number of technologies and pieces of equipment for separating impurities. In case of separating impurities from the mass of small seeds, especially vegetable and flower seeds, the use of separation on sieves is very expensive because compared to other crops, vegetable seeds are produced in small quantities (except for beans, peas, lentils, etc.) and have a wide variety of characteristics. Vegetables belong to a large number of plant families. This is why their seeds have a very different structure, shape, size and chemical composition. To overcome these challenges, the experimental model Seed conditioning module for vegetable species – MCSL, which separates impurities by using the aerodynamic properties of the seeds was developed. Seed conditioning module for vegetable species is designed to improve the technologies of organic seed production for vegetable seeds, flowers, industrial plants, cereals and to solve practical problems regarding seed production in the case of vegetable crops. Starting from these considerations, the paper will present theoretical and experimental information on the influence of some factors on the aerodynamic properties of cereal seeds, vegetables and industrial plants. The quality of seed separation in this module depends on the degree of uniformity of the air velocity field in the working area, on the stability of this field and on its extent.

Tomato seed value chain analysis and seed conditioning among seed companies in Uganda

Tomatoes increase nutritional food security and income among Ugandan smallholder farmers who have limited access to high quality seed. The objective of this study was to analyze the current tomato seed value chain for Uganda. Survey responses determined roles of key participants, including Ministry of Agriculture, Animal Industry and Fisheries (MAAIF) for regulation and certification; National Agricultural Research Organization for breeding cultivars and seed multiplication; Makerere University for education and research; commercial seed companies for seed importation and conditioning; seed distributors for sales; and smallholder farmers as savers and end users of seed. Challenges included an inefficient domestic seed distribution system, technical constraints in seed production and conditioning by seed companies, inadequate networks and communication among the seed industry’s key participants, and partial regulation of the seed industry. Seed companies played a key role in seed conditioning processes. Companies imported all tomato seeds into Uganda and stated germination as their primary goal for quality. Challenges for seed companies included assistance from MAAIF to regulate and certify seed and access to improved technologies. Attaining high quality seed by commercial Uganda-parent companies will require additional investment and training of seed technologists for domestic testing and seed quality assurance.

Seed conditioning process in the sanitary quality of marandu grass seeds

The purpose of seed conditioning process is to separate seeds and their associated structures into different fractions and retain only good and healthy seeds. Thus, the aim of this study was to evaluate the effects the stages of seed conditioning have on the sanitary quality of marandu grass seeds. The seeds were sampled before and during the seed conditioning process, i.e., after exiting the air-screen cleaner and sieves (seeds discharged from the top, middle and bottom sieves), the first gravity separator (seeds drifting around the table, upper and intermediate discharge) and second gravity separator (upper, intermediate and lower discharge). The sanitary analysis was performed using the filter paper method with and without surface disinfestation of the seeds, which were incubated at 20±2°C, with a photoperiod of 12 hours for seven days. The experiment was conducted in a completely randomized design, in a 2x6 factorial scheme (surface disinfestation x stages of the seed conditioning process) and ten replications. The data was submitted to analysis of variance, using the F test and, when significant, the means of the treatments were compared using the Tukey test at 5% probability. It was concluded that it is not possible to improve the sanitary quality of marandú grass seeds through the seed conditioning process.

Germination Energy and Capacity of Maize Seeds Following Low-Temperature Short Storage

The present research attempts to characterize the effect of low temperatures, and the moisture content of maize (Kosmo 230) meant for sowing on its energy and capacity to germinate. Seeds were moistened to varying degrees and stored under various conditions; then, their germination energy and capacity were assessed. Sowing material with 15% moisture content showed slightly declined germination ability when stored at −25–−20 °C for over three days, while the storage of seeds with a 25 and 30% moisture content at −5–0 °C for 1–3 days had the effect of seed conditioning. Seedlings obtained from conditioned seeds showed sustainability characterized by faster growth, and demonstrated nearly twice the size as other plants. Warehousing and storage of maize grains with a 11.12% moisture content at temperatures up to −25 °C did not significantly affect seed germination capacity or energy, irrespective of storage time.