QUALITY BREEDING IN RICE

1. QUALITY BREEDING IN RICE
PRESENTED BY,
SANDESH,G.M
2016610811
TNAU, MADURAI

2. INTRODUCTION
• Rice is the world most important staple food crop and is primary food source for about half of
the world’s population.
• Rice yields were greatly enhanced by the development of semi- dwarf cultivars in 1960s.
• In recent years breeders and scientists have focused on improving the quality of rice for
different purposes and markets.
• Several aspects of rice kernel are taken into consideration for determining quality. These
include appearance of endosperm, length and shape of kernel, milling quality, cooking quality,
aroma, protein content, etc.

3. FOUR TRAITS OF RICE GRAIN QUALITY
MILLED QUALITY
MILLED RICE RECOVERY
HEAD RICE RECOVERY
APPEARANCE QUALITY
GRAIN LENGTH
GRAIN WIDTH
GRAIN L/W RATIO
CHALKINESS DEGREE
COOKING QUALITY
AMYLOSE CONTENT
GELATINISATION TEMPERATURE
GEL CONSISTENCY
NUTRITIONAL QUALITY
PROTEIN CONTENT
LYSINE CONTENT
MICRO NUTRIENTS

4. CONVENTIONAL BREEDING FOR EATING AND
COOKING QUALITIES IN RICE
• Conventional breeding was implemented in the past to improve and develop
varieties with better eating and cooking qualities.
• Jennings (1979) stressed that conventional backcrossing is useful for selecting
traits that are controlled by a single gene.
• However, grain quality is controlled by quantitative trait loci (qtl), which show
continuous phenotypic variation and lack discrete phenotypic segregation in the
progeny (yano and sasaki, 1997).
• Conventional breeding techniques have encountered difficulties in improving
the cooking and eating quality traits ( wendy , 2014).

5. IMPROVEMENT BY BACKCROSSING METHOD
• Conventional backcrossing program between peta, which was released in 1940, and belle patna,
released in 1961 (jennings , 1979).
• Peta has chalky endosperm and a low gelatinization temperature, whereas belle patna has clear
endosperm and an intermediate gelatinization temperature.
• Individuals with eating and cooking qualities similar to belle patna will be selected and crossed
with peta.
• After a series of backcrosses, the end products are lines with a morphology similar to that of
peta, besides having grains similar to those of belle patna (wendy , 2014).

6. IMPROVING QUALITY BY QTL PYRAMIDING IN RICE
• Large numbers of quantitative trait loci (QTL) affecting rice quality traits have
been identified and mapped in various mapping populations (xing and zhang,
2010), in order to apply marker assisted selection (MAS) to improve breeding
efficiency.

7. MAPPING OF GRAIN LENGTH QTLS IN RICE
• Grain dimensions (length, breadth and length/ breadth ratio) are quantitatively inherited, it is
difficult for the breeders to efficiently improve grain appearance using conventional selection
methods (mckenzie and rutger, 1983; tan , 2000).
• Lin (1995) identified twelve qtls for grain dimensions, including five for grain length, two for
grain breadth, and five for grain thickness on chromosomes 5, 6 and 7.
• A consistent qtl for grain length has been mapped on rice chromosome 7 (grl7-1, qgl7, qgl7-2)
using three different mapping populations (amaravathi , 2008; bai , 2010; shao , 2010).
• Singh (2012) identified two significant quantitative trait loci (qtl) intervals on chromosomes 1
and 7 for grain dimensions in basmati rice using a population of recombinant inbred lines (rils)
from cross between basmati variety pusa 1121 and a short grain non-aromatic variety pusa
1342.

8. COOKING QUALITY
• Basmati, the aromatic rice praised for its unique quality, is a natures gift to
indian sub-continent.
• It is cultivated on the foot hills of the himalayas in the northwestern parts of
indian sub-continent comprising.
• The states of haryana, punjab, Uttaranchal, western uttar pradesh, jammu &
kashmir, himachal pradesh and delhi.
• Sugadhmati, pusa sugandh 4, pant sugandh dhan 17, geetanjali, rajendra sweta,
bhogavati, mugad sugandha, yamini and vasumati.

9. AROMATIC SHORT GRAIN RICES
• India abounds with scores of indigenous aromatic short grain cultivars and land
races, grown in pockets in various states.
• Precise area under their cultivation is difficult to ascertain. With the exception of
shorter grain length and shape, they possess aroma, specific adaptation and
excellent cooking and eating quality traits similar to basmati rices .

10. SHORT AND AROMATIC GRAINS IN INDIA

11. AMYLOSE CONTENT
• Amylose content (AC) is considered the single most important character for
predicting rice cooking and processing behavior.
• Studies on the inheritance of amylose content have shown involvement of one
major gene and several modifiers with high amylose content incompletely
dominant over low.
• Kumar and khush (1986) reported complete dominance of high amylose content
over those of low and intermediate amylose content.
• The role of at least two complementary genes in addition to the waxy gene was
indicated by stansel (1966)

12. CONTD..,
• The synthesis of amylose is catalyzed by the granule-bound starch synthase
(GBSS protein), which is known to be encoded by the rice waxy (wx) locus
(okagaki & wessler, 1988).
• An antisense wx gene aimed at reducing their amylose content.
• Amylose content was reduced to less then 2%.

13. TRANSGENIC APPROACH FOR NUTRITIONAL QUALITY
GOLDEN RICE :
• Golden rice was created by transforming rice with two beta-carotene
biosynthesis genes.
1.Psy(phytoene synthase)from daffodil(narcissus pseudonarcissus)
2.Ctrl(carotene desaturase)from the soil bacterium (erwinia uredovora).
By adding only two genes, a plant phytoene synthase (psy) and a bacterial
phytoene desaturase (crt i), the pathway is turned back on and β-carotene
consequently accumulates in the grain.

14. GOLDEN RICE 2
• It was produced by syngenta in 2005.
• It is produced by combining phytoene synthase gene from maize with crt1 from
the original golden rice.
• Golden rice 2 produced 23 times more carotenoids than golden rice.

15. PROTEIN CONTENT
• Biofortification of rice with the essential amino acid lysine.
• The direct approach involves expressing recombinant storage proteins with abundant lysine
profiles, such as overexpressing lysine-rich proteins, in grains of rice (wong. Et al., 2015).
• The second approach is to modify seed storage proteins. For example, silencing the gene
encoding the 13-kda prolamin increased total lysine content by 56% and altered nutritional
quality in rice (kawakatsu et al., 2010).
• The third approach is to use metabolic engineering, which has been used to regulate the key
genes involved in lysine metabolism to increase lysine content in plants (zhu and galili, 2003;
long et al., 2013).

16. CYSTEINE
With the aim of increasing the cysteine level in rice (oryza sativa L.) And thus
improving its nutritional quality, transgenic rice plants were generated .
• Enzyme used: escherichia coli serine acetyltransferase isoform (ecsat)
• It synthesis o-acetylserine, the precursor of cysteine.
• The contents of cysteine and glutathione increased 2.4-fold and 2-fold, respectively.

17. • Free methionine increased in leaves up to 2.7-fold, in seeds up to 1.4-fold, and
bound to seed proteins up to 4.8-fold, respectively.
• As the transgenic rice plants over expressing ecsat had significantly higher
levels of both soluble and protein-bound methionine, isoleucine, cysteine, and
glutathione in rice lead for improving the nutritional quality of rice.

18. IRON CONTENT
• Transgenic approach was used to increase fe content in rice.
• APPROACH 1:
• Enhancing fe accumulation in seeds
fe storage protein, ferritin gene under the control of
Endosperm specific promoters. Increases by 2-fold.
SoyferH1,
SoyferH2

19. • APPROACH 2:
ENHANCING FE TRANSPORT WITHIN THE PLANT BODY BY THE OVER
EXPRESSION OF NAS. INCREASED BY 3-FOLD.
• APPROACH 3:
ENHANCING FE INFLUX TO SEEDS BY EXPRESSION OF THE FE(II)NA TRANSPO
RTER GENE
UNDER THE CONTROL OF THE OSSUT1 PROMOTER. FE CONTENT
INCREASED BY 4-FOLD.
OsYSL2

20. REFERENCES
• Historical significance, grain quality features and precision breeding for improvement of export
quality basmati varieties by Manish K pandey and Injey sudharshan.
• Improvement of the eating and cooking qualities of rice: a review by Ali sattari1*, Nafiseh
Mahdinezhad2, Baratali fakheri2, M Noroozi3 and Haj Beheshtizadeh.
• Simultaneous improvement for four quality traits of zhenshan 97, an elite parent of hybrid rice,
by molecular marker-assisted selection BY P. H. Zhou, Y. F. Tan,Y. Q. He, C. G. Xu and Q. Zhang
• Stable inheritance of the antisense waxy gene in transgenic rice withreduced amylose level and
improved quality by Qiaoquan liu, Zongyang wang and Xiuhua chen.
• Biofortification of rice with the essential amino acid lysine by Qing-Qing yang, Chang-quan zhang
and Man-ling chan.

21. THANK YOU..,