Assessment of the Initial Temp of Growth of Sudangrass, Sorghum × Sudangrass Hybrids and Sweet Sorghum Forms

Abstract

One of the basic factors limiting the wider use of sudangrass, sorghum × sudangrass hybrids and the sweet sorghum forms is the necessity of late sowing, which does not allow using the entire productivity potential of these crops. The selection of genotypes, adopted for germination and fast initial temp of growth in lower temperatures is of extreme importance for the real application in agricultural practice. The differences between the tested laboratory methods for assessment of seeds are significant especially for the eye vigor index. The variation between the genotypes for the most of them is proved. The dry matter content is almost twice higher for the variant with Petri, because of the maintenance of more humid media for the variant with filter paper harmonics. For the last variant is noted significantly longer root for the sake of the eye. The chosen variant with soil mixture and temperature of 10 – 12 ºС simulates successfully the limiting factors of the practice in the Northern Bulgaria conditions. The influence of the genotype is expressed very strongly, and the most susceptible are the sweet forms of sorghum. These results confirm the effectiveness of the application of laboratory methods for assessment and selection of adopted to the local conditions genotypes of Sudangrass, Sorghum × Sudangrass hybrids and sweet forms of sorghum.