Presentation on theme: "DR. Paul Njiruh Nthakanio………TUK Dr. James I. Kanya …………………UoN Dr. John M. Kimani ………………...KARI Mwea Dr. Raphael Wanjogu ………………MIAD FUNDED / COLLABORATORS."— Presentation transcript:
DR. Paul Njiruh Nthakanio………TUK Dr. James I. Kanya …………………UoN Dr. John M. Kimani ………………...KARI Mwea Dr. Raphael Wanjogu ………………MIAD FUNDED / COLLABORATORS NATIONAL IRRIGATION BOARB, TUK, UoN, KARI
Work started in 2011 under NCST funding. In 2012, we approached NIB which agreed to support the project financially. Project is being conducted in four phases Phase one: Adaptability of breeding rice lines in Kenya at KARI Mwea (In green house and natural conditions):-Done Phase Two: Breeding. Hybridization between Basmatis (370 and 217 ) as paternal parents and PGMS and TGMS rice lines (Obtained from IRRI):- On going. Phase Three: Natural sterility induction in Mombasa; On going. HYBRID RICE PROJECT
Phase 4: Production of hybrid rice in Bunyala and Mwea. Publication Kanya J.I., Njiru P.N., Kimani J.N., Wanjogu R.K. (2013): Evaluation of Photoperiod and Thermosensitive Genic Male Sterile Lines For Hybrid Rice Seeds Production in Kenya. International Journal of Agronomy and Agricultural Research ( (Print) (Online) Vol. 3, No. 2, p , 2013).
1.1 Background : Rice production in Kenya Over 300 tonnes of rice is consumed in Kenya. About 100 tones is locally produced. In Kenya rice is mainly grown in Mwea, Ahero, Bunyala, West Kano, Yala Swamp (MoA, 2011). About 98% of Mwea rice is Basmati. By year 2030 Kenya population is expected to be 60.0million. Rice yield is expected to increase 600% to feed the population.
Year Kenya Population 38m40m60m?? Production (Tones) 64,840100,00?? Area (ha)23,106?? Table1. Source: NCPB and Department of Land, Crops Development and Management, USDA
Global Concerns High yielding varieties (HYV) dwarf rice varieties have reached breeding plateau hence global yield. Green revolution technology now need re- innovation.
Low yield per hectare of Basmati rice (4.1ha) (Ministry of Agriculture, 2010). Rice consumption is far above production. Rice diseases like blast continue to reduce yields (Wanjogu and Mugambi, 2001).
Hybridization has been used to increase rice yield per hectare (Zhang, 2010). High yield is due to heterosis or hybrid vigour.
1.5 Measuring heterosis? Mid-Parent (MP) heterosis (F1 performs better than mean of two parents): F1-MP MP X100 Better Parent (BP) heterosis (F1 performs better than better parent): Standard heterosis (F1 performs better than the check variety): F1-BP BP X100 F1-CK CK
To make a cross Male and female parents are needed. a) Female need to have non-viable male gametes so that they can be crossed with another variety. b) Male parent: need to have viable pollen.
x Female with sterile pollen but fertile ovule. Male parent with fertile pollen Hybrid plant
Male emasculation is done to induce m ale sterility, a condition in which the pollen grains are not viable to fertilize normally to set seeds. Methods of male emasculation a) Environmental Genic Male sterility method (EGMS) ‣ PGMS – photoperiod sensitive genic male sterile lines. Uses long daylight length to induce sterility ‣ TGMS - thermosentive genic male sterile lines Uses high temperature to induce sterility
b) Cytoplasmic genetic male sterility (CMS) Male sterility is controlled by the interaction of a genetic factor (S) present in the cytoplasm and nuclear gene (s). c) Chemically induced male sterility Male sterility is induced by some chemicals (gametocides).
. Based on the discovery of P(T)GMS mutant Male sterility controlled by 1 or 2 pairs of recessive gene(s) Fertile S-line Multiplication Critical Fertility Point Critical Sterility Point Reproductive Upper Limit Reproductive Lower Limit Sterile F1 Seed Production Partial Sterility Model of Sterility / Fertility Expression for TGMS Rice Temperature low high
Use hybrid rice technology to raise yield i ) Introduce EGMS in Kenya and test for their adaptability. ii) Develop Basmati with EGMS gene. iii) Produce hybrids by crossing EGMS-Basmati with conventional Basmati.
EGMS included; PGMS and TGMS LINES FROM IRRI. These are:- PGMS Lines V1 - IR S V3 - IR S TGMS Rice V2 - IR S. Basmati370
Test for EGMS adaptability Sowing of EGMS in KARI Mwea. Growth at sterility conditions and spikelet fertility assessed. Growth under fertility inducing conditions and spikelet fertility assessed.
a b Fig. a and b show EGMS and the greenhouse respectively
a b c a). EGMS under sterility inducing conditions, b). sterile panicle and c). Pollen from sterile panicle.
a b C a). EGMS rice plant, b). Panicles and c). Pollen from plants grown under fertility inducing conditions respectively with grains.