Effect of Silica on Rice Agromorphological Diversity Under Iron Toxicity Conditions in Lowland Rice of Guinea Conakry

Abstract

Rice is the second most important cereal in West Africa and is an essential element in the diet of the population. However, iron toxicity is one of the major edaphic constraints in lowland rice cultivation. The large amount of ferrous ions in solution causes an imbalance in nutrients involving a nutritional disorder affecting the growth of crops including rice. The present study conducted in 2014 in Guinea Conakry in the lowlands of the Kilissi Agronomic Research Station aimed to evaluate the effect of silica on reducing of the effect of iron toxicity in rice. Thus, rice varieties were evaluated according to a split plot device with three (3) randomized replications for two factors (rice varieties and silica doses) and three (3) silica treatments (D0 g, D120 g and D240 g). The results showed a significant effect of silica on most agronomic parameters of the rice varieties tested. The D240 g dose gave the

Assessment of genetic diversity of local rice accessions cultivated in Guinea revealed by SNPs markers, and identification of markers associated with tolerance to iron toxicity

“…Thus, to improve rice productivity in iron toxicity affected areas, one of the easily accessible and economically profitable avenues for local producers is the use of local iron stress tolerant or resistant cultivars. In addition, previous studies using morphological markers (Barry et al, 2019a;Barry, 2006) revealed the existence of agromorpho-physiological variability and a positive effect of silica on reducing iron toxicity. However, morphological traits, although they are the primary tools used in breeding programmes, are generally not very informative because of the strong influence of the environment (Anderson et al, 2006).…”

“…Also, several technological packages such as the development of tolerant or resistant varieties by the Africa Rice Center and the use of silica or fertilisers have been put in place to combat iron toxicity. However, farmers still face enormous difficulties related to the problem of largescale dissemination of these varieties, their adaptation, the availability of silica, the high cost of fertilisers and the lack of development of plains (Barry, 2020;Barry et al, 2019a). The low success of these previous works in developing iron toxicity tolerant varieties is also related to the complexity of tolerance to this stress in rice.…”

Genetic Diversity of Local Rice Accessions Cultivated in Guinea Based on Agro-Morphological Traits and Identification of Sources of Tolerance to Iron Toxicity

“…In Guinea, iron toxicity is much more prevalent in the lowlands of Lower Guinea and Forest Guinea. Despite the numerous works carried out by the Guinean Agricultural Research Institute in collaboration with Africarice to subdue the effects of this abiotic constraint through the creation of new varieties (ARICA6, ARICA18, NERICAL19, CK73) created by AfricaRice, IRRI and Kilissi that are iron-tolerant or iron-resistant, and through the use of alternative methods such as silica [14] or fertiliser, iron toxicity still hinders the development of rice production in Guinea. Indeed, farmers still face enormous difficulties related to the problem of large-scale dissemination of improved varieties, their adaptability, the availability of silica, the high price of fertiliser, and the lack of development of plains [1].…”