Informations et ressources scientifiques
sur le développement des zones arides et semi-arides

Accueil du site → Doctorat → Kenya → Growth and Physiological Response of Seven Amaranth Species to Soil Water Deficit

Maseno University (2018)

Growth and Physiological Response of Seven Amaranth Species to Soil Water Deficit

JOMO, Oscar Mbera

Titre : Growth and Physiological Response of Seven Amaranth Species to Soil Water Deficit

Auteur : JOMO, Oscar Mbera

Université de soutenance : Maseno University

Grade : DOCTOR OF PHILOSOPHY IN BOTANY (PLANT ECOLOGY) 2018

Résumé partiel
Soil water deficit is a principal abiotic factor that limit plant growth and development in dry areas. Insufficient moisture contribute to soil water deficit and some negative effects on plants such as reduced growth, yield, altered biomass allocation, reduced photosynthesis and decreased plant survival. Differences in soil water deficit responses of plants may be a consequence of different physiological and morphological adaptations. In arid and semi-arid areas, water shortage is becoming an increasing problem because of the unreliable and limited rainfall and it significantly contributes to food shortage especially in Kenya. Amaranth species are among the most popular and widely consumed micronutrient rich African indigenous leafy vegetables in Kenya ; however, published information is limited conceming growth and physiological response of amaranth species to soil water deficit. This research was therefore designed to evaluate the response of seven widely cultivated amaranth speciesin Kenya :- Amaranthus blitum (L), Amaranthus retrojlexus (L), Amaranthus spinosus (L),Amaranthus albus (L), Amaranthus cruentus (L), Amaranthus hypochondriacus (L) and Amaranthus tricolor (L). to soil water deficit in relation to their growth and physiology. The experimentwas carried out at Kenya Agricultural and Livestock Research Organisation, Kisii Centre. The experiment was laid out as completely randomized design, consisting of four treatments, seven species and three replications. The treatments were : watering daily (TI), watering every 3 rd and 6 th day (T2), watering every 9 th day (T3) and watering every lih day (T4). Seeds of the seven amaranth species were grown in 20 litre plastic pots in loam moist soils having a pH of around 4.6 to 5.4 in a glasshouse condition. Data collections commenced on the twelfth day before initiating treatments and were collected after every twelve days. Growth parameters measured included ; shoot height, stem diameter and root to shoot ratio. Gas exchange parameters were determined from one leaf per plant per treatment per replication and this included, stomatal conductance, net carbon (iv) oxide assimilation rate, intercellular carbon (iv) oxide concentration and transpiration rate by use of a portable infrared gas analyzer.

Présentation

Version intégrale (67,2 Mb)

Page publiée le 23 juin 2022