Browsing by Author "Rodrigues, Miguel"
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- Manual técnico da macieiraPublication . Antunes, Gonçalo; Freitas, Graça; Freitas, Gregório; Nóbrega, Humberto; Freitas, Isabel Tomás; Neto, Manuel; Rodrigues, Miguel; Dantas, Luís Miguel; Nunes, Rui; Carvalho, Miguel A. A. Pinheiro de
- Screening for drought tolerance in thirty three Taro cultivarsPublication . Ganança, José F. T.; Freitas, José G. R.; Nóbrega, Humberto G.M.; Rodrigues, Vanessa; Antunes, Gonçalo; Gouveia, Carla S. S.; Rodrigues, Miguel; Chair, Hana; Carvalho, Miguel A. A. Pinheiro de; Lebot, VincentTaro [Colocasia esculenta (L.) Schott] is a root crop which is an important staple food in many regions of the world, producing 10.5 million tonnes on 1.4 million hectares a year. The crop is cultivated in wet (rain fed) or irrigated conditions, requiring on average 2,500 mm water per year, and in many countries it is cultivated in flooded plots. It is estimated that taro production could decrease by 40% as a result of the increase in drought and other severe events. In this work, thirty three accessions, including local cultivars, selected and hybrid lines were submitted to long duration drought stress and screened for tolerance. Twelve physiological, morphological and agronomic traits were measured at harvest, and subject to multivariate analysis. Stress indices, Water Use Efficiency and Factorial Analysis were useful for discriminating accessions regarding drought tolerance and yield stability, and drought tolerant and susceptible cultivars were identified. Our results confirm that different taro cultivars have different drought avoidance and tolerance strategies to cope with water scarcity. Better yield performers minimised biomass and canopy loss, while tolerance was observed in cultivars that presented low potential yield, but efficiently transferred resources to enhance corm formation. Among the 33 accessions, two local cultivars showed high yield stability and could be considered as suitable parents for breeding programs, while two others are well adapted to drought, but with overall low yield potential.
- Screening of elite and local taro (Colocasia esculenta) cultivars for drought tolerancePublication . Ganança, José Filipe T.; Freitas, José Gregório F.; Nóbrega, Humberto Gil M.; Rodrigues, Vanessa; Antunes, Gonçalo; Rodrigues, Miguel; Carvalho, Miguel Ângelo A. Pinheiro de; Lebot, VincentTaro (Colocasia esculenta (L.) Schott) is a vegetative propagated tropical root occupying the 9th position among world food crops. Taro is an important staple food for many local populations of Asia and Africa. The crop is dependent of wet and highly irrigated growth conditions. Under the scenario of undergoing climatic changes, is estimated that taro production could decrease in the next 30 years as result of drought constraints. The project EU Aid Taro, DCI-Food/2009/45 “adapting propagated crops to climatic and commercial changes” aims to study ways to adapt this clonally propagated root to these climatic changes. A set of drought stress assays were realized at ISOPlexis Genebank (Madeira University), using local taro cultivars (Macaronesian taro genepool) and elite cultivars and seedlings provided by the Secretariat of the Pacific Community (SPC). The 1st pilot assay was realized in a small greenhouse, included 3 local cultivars and aimed to modelate the wattering regimes and their influence on crop growth. The 2nd full assay was realized in two greenhouses, during a full plant growth cycle. Thirty four taro cultivars, 15 elite lines provided by SPC, and 19 local cultivars, from Madeira (10), Canary Islands (6), Azores (2), and Cyprus (1) were screened. Plants were individually cultivated in pots under 2 contrasting wattering regimes, high (0,36 liters/day) and low (0,18 liters/day ). Data for 14 morpho-agronomic traits, biomass and yield parameters were collected from 5 plants for each cultivar, per treatment.