Drought, heat stress, and unfavorable soil conditions are key abiotic factors affecting quinoa’s growth and development. The aim of this research was to examine the effect of progressive drought and N-fertilization reduction on short-cycle varieties of quinoa (c.v. Titicaca) for different sowing dates during the dry season (from October to December). A two-year experimentation (2017–2018 and 2018–2019) was carried out in Burkina Faso with four levels of irrigation (full irrigation—FI, progressive drought—PD, deficit irrigation—DI and extreme deficit irrigation—EDI) and four levels of N-fertilization (100, 50, 25, and 0 kg N ha−1). Plant phenology and development, just like crop outputs in the form of yield, biomass, and quality of the seeds were evaluated for different sowing dates having different temperature ranges and photoperiodicity. Crop water productivity (CWP) function was used for examining plant’s water use efficiency under drought stress conditions. Emerging findings have shown that CWP was highest under DI and PD (0.683 and 0.576 kg m−3, respectively), while highest yields were observed in 2017–2018 under PD and its interaction with 25 to 50 kg N ha−1 (1356 and 1110 kg ha−1, respectively). Mean temperatures close to 25 °C were suitable for optimal plant growth, while extreme temperatures at anthesis limited the production of grains. Small changes in photoperiodicity from different sowing dates were not critical for plant growth.

The aim of this study was to determine the possibility of amaranth cultivation in Central Italy and to determine the optimum plant density. Field trials were carried out in 2011 and 2012 under non-irrigated conditions in Tuscany (43° 18' N, 11° 47' E). Twelve accessions of two amaranth species (Amaranthus cruentus L. and A. hypochondriacus L.) were utilised. Genotypes were evaluated over a two-year period using a RCB design with three replicates. The effects of plant density were investigated in 2012. A with a split-plot design was used, where the A. cruentus accessions (AMES 5148, PI 511719 and PI 643045) constituted the main plots. Plant densities (7.5, 15, 30 and 60 plants m -2 ) constituted the subplots. Plants were transplanted at the 3-4 true leaf stage. Morphological traits were determined using 5 plants selected from the two central rows of the sampling area. Plots were hand-harvested and cleaned with a mechanical grid with appropriate sieve diameters. A. cruentus was shown to be more suitable to the Central Italy agro-ecological conditions than A. hypochondriacus. The accessions derived from Mexico (PI 477913, PI 576481, PI 643045, PI 643053, and PI 6495079), Guatemala (PI 511719) and Puerto Rico (AMES 5148), had both higher grain yields and a greater stability over the two-year period, with a mean grain production ranging from 2.8 to 3.2 t ha -1 . The severe climatic stress in 2012 (high temperatures and aridity), resulted in a 43-60% reduction in seed production compared to that of the previous year. Under these conditions, PI 511719, AMES 26015, AMES 5386, AMES 5148, PI 477913 yielded on average 1.9 t ha -1 . Yields of A. hypochondriacus were negligible in both years, probably attributable to greater photoperiod sensitivity, resulting in reduced flowering and delayed maturity. By increasing density up to 60 and 30 plants m -2 for PI 511719 and AMES 5148, respectively, grain production was increased by 55%. As the plant population increased, plant height, panicle length and diameter, basal stem diameter and branches per plant were reduced. AMES 5148 plants were composed of one single stem with apical panicles at a density of 30 plants m -2 , whilst the other two accessions were similar at the highest plant density. Branch number per plant was negatively correlated with grain production (r=-0.536**). Hence, A. cruentus may be grown in Central Italy even under arid conditions, using a density of either 30 or 60 plants m -2 according to the genotype used.

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We analyze an oligopolistic microcredit market characterized by asymmetric information and institutions that can offer only one type of contract. We study the effects of competition on contract choice when small entrepreneurs can borrow from more than one institution due to the absence of credit bureaus. We show that appropriate contract design can eliminate the ex-ante incentives for multiple borrowing. Moreover, when the market is still largely unserved and particularly risky, a screening strategy leading to contract differentiation and credit rationing is unambiguously the most effective to avoid multiple borrowing.