Adaptation of various maize hybrids when grown for biomass

M.V. Radchenko¹*, V.I. Trotsenko¹1, A.O. Butenko¹, І.M. Masyk¹, Z.I. Hlupak¹, O.I. Pshychenko¹, N.O. Terokhina², V.M. Rozhko³ and O.Y. Karpenko³

¹Sumy National Agrarian University, Faculty of Agrotechnology and Nature Management, Department of Agrotechnologies and Soil Science, 160 g. Kondratieva street, UA40021 Sumy, Ukraine
²Sumy National Agrarian University, Department of Foreign Languages, 160 g. Kondratieva street, UA40021 Sumy, Ukraine
³National University of Life and Environmental Sciences of Ukraine, Agrobiological faculty, Department of Agricultural and Herbology, 15 Heroiv Oborony street, UA03041 Кyiv, Ukraine
*Correspondence: radchenkonikolay@ukr.net

Abstract:

The aim of this research is to optimize growth and development of maize for biomass by selecting maize hybrids to fulfill their productivity potential. The following maize hybrids were the subject of research: Forteza, DM Native, DM Skarb. The greatest height of plants was formed in the interphase period of milk-wax maturity of grain in hybrid Forteza – 286.4 cm. In hybrid DM Native the height of plants was – 271.2 cm, hybrid DM Skarb – 263.6 cm. Weight of one plant of hybrids studied during the maize growing season ranged from 442 g to 760 g. Thus, the largest mass of maize plants was recorded in the milk-wax maturity stage. It was the largest at the hybrid Forteza and amounted to 760 g, that is more than at the hybrid DM Native for 3.4% (26 g) and at the hybrid DM Skarb for 6.6% (50 g). The average crop yield of the hybrid Forteza for the period of research was 55.1 t ha^-1. Hybrids DM Native and DM Skarb provided this indicator at the level of 50.6 and 45.7 t ha^-1 respectively. Hybrid Forteza provided a maximum crop yield 55.1 t ha^-1 with plant height 286.4 cm, assimilation surface of one plant and a crop 0.59 m²; 42.8 thousand m² ha^-1 and plant weight 760 g.

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Temperature distribution analysis inside the strawberry flower head

M. Pennar*, V. Palge, E. Kokin, K. Jürjenson, E. Ideon and A. Annuk

Estonian University of Life Sciences, Institute of Technology, Kreutzwaldi 56, EE51014
Tartu, Estonia; *Correspondence: madis.pennar@emu.ee

Abstract:

Different studies by numerous researchers were carried out recently to describe different heat flux components of heat balance equations for radiation frost condition in plants. The aim of most of the papers was to present more simple and clear mathematical algebra to show the plant heat balance formulas. To achieve this aim several simplifications were made. Nevertheless there are studies reporting different flower damage rates during spring frost sessions that mentioned studies cannot explain. This leads us to the need to find the temperature distribution inside the flower to understand why during the similar energy flux conditions the flowers act against frost stress differently. It’s easy to measure the flower surface temperature but rather difficult to measure temperature distribution inside the flower head due to very small flower head scale compared to sensor sizes. To help to overcome these difficulties the authors make simplification by substituting the strawberry flower head with spherical homogeneous body though it is clear that the flower head is not homogeneous because of varying flower structure. The aim of this study is to present mathematical formulas for temperature distribution calculation inside the spherical body in terms of heat transfer conditions characteristic to radiation frost. Transient numerical methods are implemented for different conditions in case of spherical body. This approach enables us to decide if suggested mathematical solution is usable for nonhomogeneous body. Computer program was prepared to analyse the results. Key words: radiation frost, temperature distribution, plant, transient numerical method.

Key words:

plant, radiation frost, temperature distribution, transient numerical method