Open AccessOptimizing the establishment of bean and maize varieties in tropical environments
Author(s) -
José A. Andrade,
Michelle Barbosa Mateus,
Jorge Cadima,
F. G. Abreu
Publication year - 2021
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.179
H-Index - 26
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/858/1/012001
Subject(s) - germination , phaseolus , crop , horticulture , loam , limiting , zea mays , petri dish , mathematics , agronomy , biology , soil water , ecology , mechanical engineering , genetics , engineering
The successful establishment of any crop is the initial indication of its productivity. Optimizing the establishment of a crop implies ensuring generalized, fast and concentrated emergence. This work studies optimal temperature ranges, under non-limiting water conditions, for both germination and emergence of two bean ( Phaseolus vulgaris L.) varieties ( catarina and ervilha ) and two maize ( Zea mays L.) varieties ( matuba and sam3 ). Experiments used a thermogradient plate. Petri dishes were used for germination experiments. Emergence experiments were performed in aluminium containers filled with packed portions of a sandy loam clay textured soil. Size, speed and spread of both germination and emergence were measured at different temperatures by Cu-CuNi thermocouples. Thermal ranges with optimal counts of both germination and emergence [T o1 sz , T o2 sz ] were identified using a flattened bell curve function. Speed was maximized for either germination or emergence over thermal ranges [T o1 sp , T o2 sp ] defined using the plateau model to relate either germination or emergence rates with temperature. Ranges along which the spread of both germination and emergence are nearly minimized [T o1 sd , T o2 sd ] were identified with the aid of even-degree polynomials. The intersection of all three thermal ranges gave rise to optimal temperature ranges [T o1 , T o2 ] for germination (OTR G ) of the four varieties in study and for emergence (OTR E ) of three of them. In general, the lower thermal limit of OTRg was determined by speed (T o1 = T o1 sp ) and the upper thermal limit by size (T o2 = T o2 sz ). OTRe begins at T o1 sp for ervilha and sam3 and at T o1 sd for catarina and ends at T o2 sz for catarina and at T o2 sd for the others. The endpoints and length of both the OTR G and OTR E were also found to be crop-dependent. Thus, farmers can choose between crops and optimize their establishment. The identification of these parameters may also be useful in assessing weather forecasts and for warning systems and agro-climatic zoning. The influence of the substrate used in each experiment was also discussed.