LATVIA UNIVERSITY OF AGRICULTURE - Latvijas ...

AGRICULTURAL SCIENCES (CROP SCIENCES, ANIMAL SCIENCES)INFLUENCE OF SOWING TYPE, TIME AND RATE ON THE BUCKWHEATYIELD FORMING ELEMENTSMihails Vilcāns 1,2 , JūlijaVolkova 2 , Zinta Gaile 11Latvia University of Agriculture2Latvian Plant Protection Research Centree-mail: mihailsvilcans@inbox.lvAbstractThere is a lack of an actual information concerning cultivation of buckwheat (Fagopyrum esculentum), on the bestmethods of sowing and seeding rates. The aim of the study was to investigate changes in the buckwheat yield formingelements depending on sowing type, time and rate. Trials were established in farm “Araji”, Kraslava area, during2010. Previous crop was spring barley. Buckwheat cultivar ‘Aiva’ was used in the field trial. Sowing was done on sixdifferent dates – May 15, 20, 25 and 30, and June 4 and 9. Two different types of sowing were used – drill sowing, with4 sowing rates 200, 300, 400, 500 fertile nutlets per 1 m 2 , and the column sowing with the three sowing rates 150, 250,300 fertile nutlets per m 2 . Data analyses were run using MS Excel Two factor analyses of variance. Time of sowingand seed rate had a significant influence on the buckwheat yield forming elements. Evaluating the performance ofplant density at column sowing, it was found that plants survival rate was higher than that in drill sowing. The highestindividual productivity of the plant was observed in plots sown in columns. The yield of buckwheat was on average30-50% higher in the plots that were sown from June 4th to 9 th if compared to those sown from May 15th to 20th, i.e.earlier sowing times were not the most suitable for buckwheat sowing in 2010.Key words: buckwheat, sowing time, sowing rate, yield forming elements.IntroductionBuckwheat (Fagopyrum eskulentum) is animportant groats plant in temperate climate zone.Buckwheat is widely used in the food industry.Buckwheat products have good dietetic propertiesbecause of its easily digestible nutrients. In recentyears, the amount of buckwheat growers and cultivatedareas has increased in Latvia. Comparing the rates of1997 and 2011, the area has been increased by 100%,reaching 10.2 thousand ha (Saimniecības ..., 1997;Latvijas statistika..., 2011). Most common problemfor the buckwheat growers is relatively low yieldsof this crop. There is a lack of the actual informationabout buckwheat growing and factors influencingthe yield. There is an insufficient information of theeffect of buckwheat sowing time and rate on the yieldforming elements.The optimal time of the buckwheat sowing isone of the main preconditions for harvesting highyields. Assuming that the influence of all agriculturalmethods of crop growing form 100%, sowing termcovers 43%, fertilizing 23%, soil cultivation – 10%,rate and way of sowing – 12%, crop maintenance 4%(Slobodyan, 2004).There are two main opinions about the sowing datein literature. Some authors recognize 2 or 3 differentsowing dates (Анохин, 1960), while others concludethat buckwheat must be sown as early as possible atsingle, best sowing time.Choice of optimal sowing date should be based onthe longterm field observations and objective sourcesof information. There is considered that the sowingtime is positively dependent on the meteorologicalconditions in April and May. The sowing rateinfluences crop density and the individual plantproductivity.Increase in the sowing rate leads to diminishedindividual plant productivity. Contrary, the reducedsowing rate positively influences the crop – theindividual plant productivity increases. It couldbe explained by plant competition inside the crop.Therefore, correctly established sowing rate providesoptimal plant density, and, thereby, increases the plantproductivity (Zakarackas, 1999).Buckwheat sowing rate vary in a relatively widerange. in conventional system in areas with optimalmoisture conditions, the preferable sowing rate isabout 400 seeds per m 2 applying drill sowing method,and 300-350 seeds per m 2 by column sowing method.In areas with unstable water provision and field areasfree of weeds, sowing rates usually become lower,respectively 200-250 and 150-200 seeds per m 2(Kalinova et al., 2003).Buckwheat plant branches very well (exceptof some cultivars) and at favorable conditions aninadequate by low seeding rate has been compensatedby increasing productivity of individual plants (Tadinaet al., 2007). If there are unfavorable conditions foroptimal seed germination, buckwheat sowing ratemust be increased by 50-100 seeds per m -1 (Bryan etal., 2006).Some sources of literature propose the columnsowing method as the most optimal technique for thebuckwheat (Bryan et al., 2006; Kwiatkowski et al.,2004). However, this technique provides the yieldincreasing only at a low-input agricultural level. Thismethod should not be considered as a key to obtaininghigh yields. For example, field trials in 1953-1971Research for Rural Development 20127