Influence of grain moisture content during harvest on the maize seed germination

Abstract

Modern maize seed drying and processing technology is applied today to ensure high quality grain. The most important factor in preserving seed quality is the moisture content. The time of harvesting, drying, storage and seed conservation is determined by the seed water quantity. At the harvesting time, a lower moisture content is desirable due to seed physiological maturity as well as consequences that may be caused during seed drying. During seed storage, water in seed is maintained at the level of latency to preserve vital seed functions, for maize it is 13-14 %. Influence of different seed moisture content, during harvesting time, on maize seed quality were studied in this research. Two physiological traits of seed were observed: seed energy and germination. Material used in this research were maize hybrids ZP 434 and ZP 666. Moisture content during harvesting time was measured after drying and primary processing, two seed sizes were obtained. From the divided seed samples were taken for laboratory tests. Harvesting was done at different seed moisture content lt 25 %, 25-30 %, 30-35 % and > 35 %. Maize cobs were dried in double-pass system drier with air temperature below 42 oC. Cob moisture is measured with moisture meter (Pfeuffer). Seed was divided into two fractions according to size using sieves with mesh sizes ranging from 6.5 - 8.3 mm and 8.4 - 11.0 mm. Seed energy and germination were determined in seed testing laboratory on working samples 4x100 seed, by standard maize germination test with ISTA Rules, and Rule on the quality of seed of agricultural plants. Experimental results were calculated on average mean and total variability xx, SD i C.V. for seed energy, germination and moisture content. The three factorial analysis of variance was calculated for both germination traits (seed energy and germination), for factors: hybrid, seed sizes and seed moisture content. The results of all factors and traits had different values. The highest means of seed energy and germination in both fractions of both observed hybrids were recorded with the seed moisture content ranging from 30 to 35 %.

U cilju dobijanja što kvalitetnijeg semenskog materijala, danas je u primeni savremena tehnologija dorade i sušenja semena. Jedan od osnovnih činilaca očuvanja kvaliteta semena je voda. Količina vode u semenu određuje vreme berbe, način sušenja, skladištenja i očuvanja kvaliteta semena.U vreme berbe poželjan je manji sadržaj vode, kako zbog fiziološke zrelosti semena tako i zbog posledica koje mogu biti uzrokovane dužim periodom sušenja. Za vreme čuvanja semena voda se održava na nivou latentnosti životnih funkcija, a za kukuruz to je 13-14%. U ovim istraživanjima posmatran je uticaj različitih vlažnosti semena u toku berbe na kvalitet semena. Posmatrane su dve fiziološke osobine semena: energija klijanja i klijavost. Materijal korišćen u istraživanjima su dva hibrida kukuruza ZP 434 i ZP 666. Berba je vršena sa različitom vlažnošću semena, a posle sušenja i krunjenja, iz naturalnog semenskog materijala izdvojene su dve frakcije po krupnoći. Iz podeljenog semenskog materijala izdvajani su uzorci za laboratorijsko ispitivanje semena. Berba je vršena sa različitom vlažnošću semena, koja je bila: lt 25%, 25-30%, 30-35% i sa vlažnošću većoj od 35%. Sušenje semenskog klipa obavljeno je u sušarama tipa komora sa dva prolaza fluida za sušenje klipa kukuruza na temperaturi ispod 42oC. Ulazna vlaga klipa merena je laboratorijskim uređajima za određivanje vlage Pfeuffer. Deljenje semena na dve frakcija izvršeno je po krupnoći korišćenjem sita promera 6,5-8,3 mm i 8,4-11,0 mm. Ispitivanje energije klijanja i klijavosti rađeno je u laboratoriji za ispitivanje semena na radnom uzorku 4x100 semena po standardnoj metodi na naizmeničnoj temperaturi 20-30oC po ISTA pravilima i Pravilniku o kvalitetu semena poljoprivrednog bilja. Eksperimentalni podaci obrađeni su na srednju vrednost, standardnu devijaciju i ukupnu varijabilnost (, SD i C.V.) za sve osobine semena i svaku varijantu istraživanja. Trofaktorijalna analiza varijanse urađena je za obe posmatrane osobine semena (energiju klijanja i klijavost), za faktore: hibrid, frakcija i vlažnost semena. Dobijeni rezultati po svim osnovama, pokazuju različite vrednosti. Najveća enegija klijanja i klijavost semena utvrđeni su za seme čija je vlaga u toku berbe bila 30-35% za oba ispitivana hibrida.