By Chesly Kobua and Peter Gendua
Severe droughts have occurred and more are expected in the near future in Papua New Guinea due to the increasing frequency of El Niño events predicted by climate experts. While it is not possible to prevent El Niño to occur, it is possible to minimize the effects of El Niño on food production with appropriate interventions.
Today’s subsistence farmers are not adequately prepared for prolonged dry periods and are at risk of malnutrition and starvation. NARI has been developing and sharing information on drought coping strategies. Among them are drought tolerant crop varieties and species and/or food preservation techniques to help farmers coping with drought events.
One prominent crop on the list is rice since it is a staple food – although it is not a staple crop. Rice has the advantage to be stored over longer periods.
In its efforts to diversify and promote rice production in PNG, in relation to climate change adaptation, NARI had accessed 78 varieties of new rice from Africa from the Africa Rice Centre. These varieties are known as “New Rice for Africa” or ‘NERICA” rice.
NARI has been evaluating the varieties under PNG conditions since 2011 as part of its drought preparedness strategies.
The NERICA varieties were developed using a tissue culture technique by crossing Oryza glaberrima (African rice) and Oryza sativa (Asian rice) – the only two cultivated rice species.
The African rice is highly drought tolerant, but its productivity is lower than that of the Asian species. By crossing the two species, the resultant rice lines have, through heterosis, the desirable characters of both species.
Additional traits considered were the level of tolerance to pest and infertile soil, and vigorous vegetative growth – which contribute to early maturity.
It is yet to be scientifically tested and proven if NERICA rice can earn much better yield under PNG climatic conditions, as compared to other species already grown in the country. Such assessment would require evaluations under different environments, climates and soil types across PNG.
The introduced NERICA varieties consist of both the upland (rain fed) and paddy/irrigated (lowland) rice. The upland varieties are tested primarily for adaptability to PNG’s drought conditions while the irrigated varieties will be evaluated for wet conditions that are normally common in many regions of the country.
Since the importation of NERICA rice seeds into the country in 2011, NARI has been following set research protocols of observation nursery and preliminary evaluations. These were done to all the 78 varieties at the Momase Regional Centre at Bubia outside Lae under upland cultivation conditions.
However most varieties failed to set seeds due to the high rainfall environment. From this lesson, the preliminary observation experiments were moved to Trukai Farms at Gabmangzung near Nadzab (Morobe) and NARI’s Southern Regional Centre at Laloki near Port Moresby. These were drier environments in the following year (2012) and most varieties did well and set seeds and preliminary selections were made.
From the 78 varieties, 16 showed acceptable level of adaptability under rain fed cultivation in both Nadzab and Laloki. They comprised 10 upland and six irrigated NERICA rice varieties.
The 16 were further evaluated through Advanced Evaluation trials (fully replicated trials) under rain fed (10 upland varieties) and irrigated conditions (six lowland varieties) at Laloki for two cropping seasons.
Right now the NARI Rice and Grain team is undertaking data collection and processing. Once potential varieties are identified, further genetic by environment (G x E) trials will be carried out under different agro-ecological environments across PNG. From there, best variety/ies will be identified, recommended and released to farmers for general cultivation.
Current evaluations and selections focus on potentials such as improved yield and ability to withstand pest and disease attacks under PNG environmental conditions.
Further tests will be done on the selected varieties, looking at eating quality, tolerance to weed competition and low soil fertility, and other factors.
Results from the advanced evaluation studies generally show that the overall growth and development performance of the promising upland NERICA rice varieties were deemed acceptable under upland cultivation conditions.
Their large grain size, early maturing capacity, tolerance to low soil moisture conditions, and ability to withstand attack of common pests are some of the features of the NERICA rice varieties that mark them as promising candidates for further screening and evaluation under PNG conditions to explore their maximum potential.
However, the promising irrigated NERICA rice varieties did not perform better than the popular Asian rice variety (NR 01). They showed higher potential yields thus further tests will be done to confirm their performance and potentials under PNG irrigated conditions.
For more information, contact the authors on telephone 478 4000 or email to [email protected]
By Chesly Kobua and Peter Gendua