Effect of irrigation and cutting intensity on yield of alfalfa

Abstract

The paper deals with the effects of irrigation and cutting intensity on the yields of forage and hay in alfalfa. In 2005 and 2006, under the conditions of irrigation after cutting, the average yields of green forage and hay were 53.45 t·ha-1 and 12.50 t·ha-1, respectively. The respective values in the variant of irrigation at 60% FWC were 53.511 a-1 and 12.24 t·ha-1. These yields were highly significant in relation to the average yields of the control, 50.58 t·ha-1 and 11.62 t·ha-1, respectively. In the fourth and fifth years of production, the systems of four and five cuts produced 49.52 t·ha-1 and 55.45 t·ha-1 of green forage, respectively. The difference was highly significant. The yields of hay amounting to 12.39 t·ha-1 and 11.78 t·ha-1 were not statistically significant. The average portions of dry matter in the systems of four and five cuts were 25.96% and 22.14%, respectively. Considering the two cutting systems together, the average numbers of stems/m2 in the fourth and fifth year were 822 and 702, respectively, i.e., the number of plants was reduced by 120 stems in relation to the previos year.

U radu se ističe uticaj navodnjavanja i frekvencija košenja na prinos zelene krme, odnosno sena lucerke. Tokom 2005. i 2006. godine, u uslovima navodnjavanja posle košenja, ostvaren je prosečan prinos zelene krme 53,45 t·ha-1, odnosno sena 12,50 t·ha-1, a navodnjavanjem pri 60% od PVK 53,51 t·ha-1, ili 12,24 t·ha-1, što je visoko signifikantno u odnosu na kontrolu (prosečno 50,58 t·ha-1 zelene krme, ili 11,62 t·ha-1 sena). U četvrtoj i petoj godini iskorišćavanja lucerke, četvorootkosnim sistemom košenja ostvareno je prosečno 49,52 t·ha-1 zelene krme, a košenjem u pet navrata 55,45 t·ha-1, te su razlike visoko signifikantne. Košenjem lucerke u četiri navrata ostvareno je prosečno 12,39 t·ha-1 sena, a sa pet košenja 11,78 t·ha-1, a razlike nisu bile značajne. U četvorootkosnom sistemu iskorišćavanja lucerke, prosečan udeo suve materije bio je 25,96%, odnosno u petootkosnom 22,14%, što je uticalo na ujednačenost prinosa sena. U četvrtoj godini iskorišćavanja i pri oba sistema košenja lucerke ostvareno je prosečno 822 stabljike/m2, a pete godine 702 stabljike/m2 ili za 120 stabljika manje u odnosu na prethodnu godinu.