Constitution of Composite Cross Maize (Zea mays L.) Populations Selected for the Semi-Arid Environment of South Madagascar

Abstract

In many African countries, such as Madagascar, a large part of the population is currently estimated to be undernourished, and self-subsistence agriculture represents the primary source of food available for the family. Smallholder farmers cultivate crops with limited agricultural input and use old landraces or obsolete hybrid varieties, with a total country-wide production that is far from being able to sustain the national food demand. In this study, we have developed two maize composite cross populations (CCPs) of different kernel colors, through a selection process among 30 half-sib lines, chosen both for their agronomic performance and their environmental adaptability to a Malagasy farm context. The best half-sib lines, identified through field tests, were clustered as a parental group for open-pollinated crosses. The new CCP created, after two years of seed multiplication in an open field, showed promising yields compared with the hybrids, parental varieties, and local landraces, with average values of 2.7 t/ha for the white CCP and 3.5 t/ha for the yellow one. The seeds produced were then distributed among 15 local farmers to begin a participatory breeding program. Our approach represents an innovative step to improve and stabilize maize yields, employing populations adapted to the cultivation environment and able to cope with different stresses, thereby helping farmers’ life conditions.

Effects of Nitrogen Fertilization and Plant Density on Proso Millet (Panicum miliaceum L.) Growth and Yield under Mediterranean Pedoclimatic Conditions

“…The identification of the best site-specific combination of D and N represents important information to improve crop grain yield and counteract the effects of climate change, reducing GHG emissions and nutrient leaching into the groundwater [30]. Overall, the present results showed that the grain yield of proso millet was slightly lower to that previously obtained in the Mediterranean area over a 3-year study conducted in Turkey (3200 kg ha −1 ) and a 2-year experiment conducted in Italy (3125 kg ha −1 ), but higher than those recorded in the United States (2016 kg ha −1 ) and India (2600 kg ha −1 ) [17,31,32]. Gong et al [24] surprisingly obtained grain yields ranging between 3500 and 4600 kg ha −1 , cultivating proso millet variety Youmi 2 in a semiarid area in China characterized by continental monsoon climate with an annual mean precipitation of 400 mm and mean temperature of 8.3 • C. However, data confirmed the lower grain yields of P. miliaceum compared with the major spring-summer cereal crops grown in the Mediterranean region, which varied from 4710 kg ha −1 to 5910 kg ha −1 for sorghum (Sorghum bicolor (L.) Moench) and from 7110 kg ha −1 to 8970 kg ha −1 for maize (Zea mays L.), confirming that extensive research is needed on the development of breeding lines for crop improvement [33].…”

Evaluation of the Agronomic Traits of 80 Accessions of Proso Millet (Panicum miliaceum L.) under Mediterranean Pedoclimatic Conditions

“…Hybrid grain cultivars have been developed for pearl millet in India and the United States, but perform best in areas where rainfall is reliable [67]. In drier areas with limited and fluctuating rainfall, where it is difficult for breeders to identify dual-purpose grain/stover modern varieties, open-pollinated varieties or composite cross population (CCP) that give stable grain and straw yields and suit the prevailing rainfall pattern, should be developed and adopted [11,68].…”

“…At the same time, climate change is accelerating land degradation and desertification, and extreme climatic events are lowering yields [6][7][8]. Global warming may reduce arable land due to the expansion of dryland regions by around 10% by the end of the 21st century, increasing global food shortages and even famine, especially in developing countries where populations are already affected by malnutrition [9][10][11]. In view of the current and future 2 of 15 scenarios, scientists suggest that an efficient strategy could be to replace high water-demanding cereal crops with drought-adopted ones, focusing on climate-resilient crops to ensure high productive and nutritional value by efficiently utilizing natural resources [12][13][14].…”

Molecular Diversity within a Mediterranean and European Panel of Tetraploid Wheat (T. turgidum subsp.) Landraces and Modern Germplasm Inferred Using a High-Density SNP Array

“…A few years ago, a novel plant breeding approach-evolutionary plant breeding (EB)relying on human selection acting on a heterogeneous population (i.e., CCPs) started to represent a valuable method for developing populations adaptable to different agricultural contexts [33,34]. Cultivation conditions can drive the selection of more adaptable genotypes that present increased fitness [35,36].…”