Enhancement of diploid Solanum chacoense Bitt. using adapted clones of Solanum phureja Juz. & Buk.

Summary F₁ hybrids between Solanum phureja and S. chacoense were studied in a new approach to enhance wild diploid potato species using adapted S. phureja clones as the female parent. S. chacoense parents had few tubers, whereas S. phureja parents had been previously selected for tuberization under long days. Twenty hybrid families were evaluated for haulm vigor, vine maturity, stolon development, frequency of tuberization, tuber set, tuber yield and average tuber weight under naturally occurring increasing or decreasing photoperiods in spring and fall growing seasons in Morocco. The hybrid plants were more vigorous, later maturing with thicker stolons in the spring season. Frequency of tuberization and tuber set did not vary with season. Tuber yield and average tuber weight were higher in fall; the maximum yield was 2.4 and 4.6 kg per hill under spring and fall conditions, respectively. Remarkable variation was found both between and within hybrid families for all traits in this first cycle of enhancement. The selection of vigorous, fertile clones incorporating the S. chacoense genome is possible by using S. phureja as an adapted germplasm source.     

Deaths and years of life lost due to suboptimal breast-feeding among children in the developing world: a global ecological risk assessment

OBJECTIVE: We estimate attributable fractions, deaths and years of life lost among infants and children < or = 2 years of age due to suboptimal breast-feeding in developing countries. DESIGN: We compare actual practices to a minimum exposure pattern consisting of exclusive breast-feeding for infants < or = 6 months of age and continued breast-feeding for older infants and children < or = 2 years of age. For infants, we consider deaths due to diarrhoeal disease and lower respiratory tract infections, and deaths due to all causes are considered in the second year of life. Outcome measures are attributable fractions, deaths, years of life lost and offsetting deaths potentially caused by mother-to-child transmission of HIV through breast-feeding. SETTING: Developing countries. SUBJECTS: Infants and children < or = 2 years of age. RESULTS: Attributable fractions for deaths due to diarrhoeal disease and lower respiratory tract infections are 55% and 53%, respectively, for the first six months of infancy, 20% and 18% for the second six months, and are 20% for all-cause deaths in the second year of life. Globally, as many as 1.45 million lives (117 million years of life) are lost due to suboptimal breast-feeding in developing countries. Offsetting deaths caused by mother-to-child transmission of HIV through breast-feeding could be as high as 242,000 (18.8 million years of life lost) if relevant World Health Organization recommendations are not followed. CONCLUSIONS: The size of the gap between current practice and recommendations is striking when one considers breast-feeding involves no out-of-pocket costs, that there exists universal consensus on best practices, and that implementing current international recommendations could potentially save 1.45 million children's lives each year.