The first sorghum [Sorghum bicolor (L.) Moench] hybrids based on West African Guinea‐race‐derived parents were created to enhance farmer's food security and income through increased yields. To assess their performance, eight hybrids, six experimental pure‐line cultivars, one pure‐line check (Lata), and a highly adapted landrace cultivar (Tieble) were evaluated in 27 farmer‐managed and two on‐station yield trials in Mali, West Africa, from 2009 to 2011. The hybrids were confirmed to have photoperiod sensitivity similar to the well‐adapted Guinea landrace check cultivar. Genotypic differences for on‐farm grain yield were highly significant and genotype × environment crossover interactions were limited. The yield superiorities of individual hybrids, relative to the landrace check, ranged from 17 to 37% over the 27 on‐farm trials. The three top yielding hybrids showed 30% yield advantages across productivity levels, with absolute yield advantages averaging 380 kg ha−1 under lower (1.0–1.5 t ha−1) and 660 kg ha−1 under higher (2.0–3.5 t ha−1) productivity conditions. A mean male‐parent (better parent) heterosis of 26% was observed for the four hybrids having Lata as a male parent. As the hybrids studied here were obtained with a low intensity of selection using a limited number of parents, even greater yield superiorities may be attained with development of distinct parental pools and scaled‐up hybrid breeding.

The genus Paraburkholderia includes a variety of species with promising features for sustainable biotechnological solutions in agriculture through increasing crop productivity. Here, we present a novel Paraburkholderia isolate, a permanent and predominant member of the Dioscoreae bulbifera (yam family, Dioscoreaceae) phyllosphere, making up to 25% of the microbial community on leaf acumens. The 8.5 Mbp genome of isolate Msb3 encodes an unprecedented combination of features mediating a beneficial plant-associated lifestyle, including biological nitrogen fixation (BNF), plant hormone regulation, detoxification of various xenobiotics, degradation of aromatic compounds and multiple protein secretion systems including both T3SS and T6SS. The isolate exhibits significant growth promotion when applied to agriculturally important plants such as tomato, by increasing the total dry biomass by up to 40%. The open question about the "beneficial" nature of this strain led us to investigate ecological and generic boundaries in Burkholderia sensu lato. In a refined phylogeny including 279 Burkholderia sensu lato isolates strain Msb3 clusters within Clade I Paraburkholderia, which also includes few opportunistic strains that can potentially act as pathogens, as revealed by our ecological meta-data analysis. In fact, we demonstrate that all genera originating from the "plant beneficial and environmental" (PBE) Burkholderia species cluster include opportunists. This indicates that further functional examinations are needed before safe application of these strains in sustainable agricultural settings can be assured.

Many farmers in West and Central Africa (WCA) prefer tall (>3 m) grain sorghum [Sorghum bicolor (L.) Moench] for various reasons. This study seeks to determine (i) what yield superiority newly bred, tall, photoperiod‐sensitive guinea‐race sorghum hybrids can provide relative to an adapted landrace variety across a wide range of productivity conditions, and (ii) the risk of these hybrids failing to provide yield superiority for individual farmers. Seven hybrids, one local check, and eight pure‐line progenies were evaluated in 37 farmer‐managed, on‐farm yield trials across three Malian zones and 3 yr. Environments were classified into four productivity groups (low [0.78–1.10 Mg ha−1], mid‐low [1.10–1.50 Mg ha−1], mid‐high [1.50–2.00 Mg ha−1] and high [2.00–2.65 Mg ha−1]) based on their trial mean grain yield. Mean yields of the seven tall hybrids were 3 to 17% (ranging from 0.06 to 0.28 Mg ha−1) higher than that of the local check across all environments and were highest (14–47%) averaged across the seven trials with the lowest mean yields. The individual overall highest‐yielding hybrid showed superiorities over the local check in the low, mid‐low, mid‐high, and high productivity levels of 0.43 (47%), 0.14 (10%), 0.47 (27%), and 0.34 (14%) Mg ha−1, respectively. The tall hybrids rarely had yields significantly inferior to the local check. Farmers’ preference for, and the possible benefits of, taller plant types may lead farmers to grow tall hybrids, particularly under the typical low‐productivity production conditions of WCA.

S orghum bicolor (L.) Moench is a major staple cereal crop in the Sahelian and savannah zones of West Africa (WA), where it constitutes the main cereal in the diet of millions, mostly living in rural areas. Yields on farmers' fields average only 100 g m −2 (1 t ha −1 ) (FAOSTAT, 2018), despite the development of new varieties (Yapi et al., 2000;Atokple, 2003). In recent years, farmers in the savannah zones of WA have replaced sorghum with early-maturing maize (Zea mays L.) varieties, especially in cotton (Gossypium hirsutum L.)-producing systems, where fertilizer is easily available (Staatz et al., 2011;Theriault et al., 2018). However, area under sorghum has been increasing in these countries (FAOSTAT, 2018), because sorghum is the cereal crop that can be grown successfully without the use of mineral fertilizer. Thus, new sorghum varieties can provide advantages to farmers, especially if they are well adapted to low soil fertility, especially low-P (LP) conditions. This is particularly important

Création variétale décentralisée Sélection participative des variétés de sorgho à l'aide d'essais multilocaux dans deux zones cibles