Dependence of the productivity of maize and soybean intercropping systems on hybrid type and plant arrangement pattern

Abstract

Intercropping systems could improve utilization of the most important resources (soil, water and nutrients), provide a better control of weeds, pests and diseases, and finally higher productivity, especially under rain-fed growing conditions. This study aimed to determine the effects of three maize (Zea mays L.) prolific hybrids (FAO 500, 600 and 700) and the spatial intercrop patterns on the above-ground biomass and grain yields of maize and soybean (Glycine max L. Merrill), on chernozem soil type at Zemun Polje, Belgrade, in 2003, 2004 and 2005. The experimental design was a complete randomized block with four replications and three treatments: 3 rows of maize and 3 rows of soybean in strips for each maize hybrid (three variants, 3 rows of maize and 3 rows of soybean in alternate rows for each hybrid (another three variants) and monocrops of both maize and soybeans. To optimize the ecological and economic benefits of maize/soybean intercrop in terms of yield, variety selection and compatibility of the component crops should be made using established agronomic management practices involving the two crops. Suitable maize varieties for maize/soybean intercrop systems are varieties that have less dense canopy. These varieties would therefore have lesser shading effect to the understory beans. However, establishment of an appropriate spatial arrangement of the component crops would be essential to alleviate negative effects especially on the less competitive crop. The intercropping system in alternate rows showed significantly higher above-ground biomass and grain yields in comparation with both the strip intercropping system and maize monocrops in 2004. Soybean gave significantly lower above-ground biomass and grain yield in intercrops than in monocrops. Maize prolific hybrid growing in intercropping with soybean as legume crop, increased productivity of cropping system, especially in favourable agroecological conditions. Maize and soybean yields reduction could have also been due to inter-specific competition for resources such as nutrients and water. Moreover, performance of the currently grown varieties in the semi-arid regions depends on the amount of rainfall received during the growing season.

Gajenjem združenih useva može se poboljšati iskorišćenost najvažnijih resursa (zemljišta, vode i hranljivih materija), obezbediti bolja kontrola korova, štetočina i bolesti, i povećati produktivnost, posebno u uslovima prirodnog vodnog režima. Cilj ovih istraživanja jeste da se utvrde uticaji tri različita višeklipa hibrida kukuruza (FAO 500, 600 i 700) i prostornog rasporeda (naizmenični redovi i trake) na prinose nadzemne biomase i zrna združenih i čistih useva kukuruza i soje. Istraživanja su obavljena na zemljištu tipa černozem u Zemun Polju, Beograd, tokom 2003, 2004 i 2005. godine. Ogledi su izvedeni po planu potpuno slučajnog blok sistema u četiri ponavljanja i tri tretmana: združeni usev kukuruza i soje u trakama za svaki hibrid kukuruza (tri varijante), združeni usev kukuruza i soje u naizmeničnim redovima za svaki hibrid (još tri varijante) i čisti usevi kukuruza i soje. U združenom usevu u naizmeničnim redovima su dobijeni značajno veći prinosi nadzemne biomase i zrna kukuruza. Ispitivani višeklipi hibridi kukuruza iz različitih FAO grupa zrenja, gajeni u združenom usevu sa sojom, imali su pozitivan uticaj na prinos, kako nadzemne biomase, tako i zrna, ali samo u 2004. godini koja je ocenjena kao najpovoljnija sa stanovišta meteoroloških uslova, posebno količine i rasporeda padavina.