crop improvement on pear & jackfruit

1. 1
breeding of pear and jackfruit
Presented by:-
Rajatiya Jignasa H.
M. Sc. (Horti.) Fruit Science
JAU, Junagadh.

2. Pear breeding
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3. Introduction
• Pear ranks second, only next to apple in many respect viz. global
importance, diversity of existence, acreage and production.
• In India pear cultivation is mainly confined to the temperate
Himalayan mountains which have ideal conditions to grow a large
number of European pear (Pyrus communis L.) and Oriental
pear (P. pyrifolia).
• However, selection and development of low chill pear cultivars
had made its cultivation possible in subtropical region of UP,
Punjab, Uttarakhand and Haryana.
• Pear fruits are consumed fresh, canned, as juice and dried.
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4. Scientificclassification
Botanical name:-
Pyrus communis (European pear)
Pyrus pyrifolia (Asian pear)
Genus: Pyrus
Subfamily: Pomoideae
Family: Rosaceae
Order: Rosales
Basic chromosome No.: 17
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5. Originanddistribution
• Probably originated in the mountainous regions of western
China where from it moved both in east and west directions.
• Vavilov (1951) proposed 3 centres of origin for the
cultivated pears
1. Chinese centre
2. Central Asiatic centre
3. Near Eastern centre/Asia minor
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6. Species
• Zeven and Zhukovsky (1975) mentioned about 60 species,
among them 22 primary species and the rest are non- primary
species which may be botanical varieties, subspecies or
interspecific hybrids.
• Bell and Hough (1986) classified all the primary species into 5
groups on the basis of geographical distribution as under:
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7. 1.Europian group
P. communis, P. nivalis, P. cordata, P.
caucasica.
2. North Africa group P. longipes, P. gharbiana, P. memorensis.
3. West Asian group
P. syriaca, P. elaeagrifolia, P.
amygdaliformis, P. salicifolia, P. glabra, P.
regelii.
4. East Asian group
P. pyrifolia, P. kansuensis, P. ussuriensis,
P. hodoensis.
5. Asian group
P. calleryana, P. betulifolia, P. fauriei, P.
dimorphophylla, P. koehnei.
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8. Salient features of very important species are given
below:
1) P. Communis (European pear)
•Trees are pyramidical in shape, medium tall and spiny when
young. White flowers are borne mostly in corymbs.
•Fruits vary in shape but mostly pyriform. Pulp is melting &
buttery in texture.
2) P. pyrifolia (Sand pear)
•Tree is tall, vigorous & spreading type.
•Fruits are mostly round (apple shaped) & very hard.
•They have crisp texture, a refreshing sweet taste but lack aroma.
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9. 3) P. pashia (Wild Himalayan pear)
•Locally known as ‘Mehal’, ‘Kainth’ or ‘Shaira’.
•Medium-sized, open-headed tree. Flowers are white & fragrant.
•Fruits are unacceptable for table purpose due to high tannin content.
•Mainly used as rootsock in India.
4) Pyrus nivalis Jacq. (French snow pear):-
• Distribution is mainly in Australia and wild in France.
• The plant is very colourful, small with thick shoots.
• It is a very hardy plant that is able to withstand a small supply of
water or very high or low temperatures.
5) P. ussuriensis Maxim. ( Siberian pear)
• It is the hardiest species known and it has proven more resistant to
pear blight than any other species.
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10. P. communis P. pashia P. ussuriensis
Pyrus nivalis P. pyrifolia
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11. Cultivars
Red Barlette Barlette Bosc
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12. Green Anjou Red Anjou Comic
Flemish Beauty Starkrimson Beaurre Hardy
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13. Cytogenetic
• It has a basic chromosome number as x=17 and suggested an
allotetraploid or allopolyploid from the cross between two
primitive forms of Rosaceae family, Prunoideae with x=8 and
Spiraeoideae with x=9.
• Most cultivated pears are diploid (2n=34), but there are a few
polypoid cultivars of P. communis and Pyrus x bretschneideri.
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14. Geneticresources
• In India, 97 accessions of pear germplasm is being maintained in
NBPGR, 56 accessions at Regional Horticulture Station,
Kotkhai. Other like RHRS Mashobra and IARI, Regional
Station, Amartara, Shimla also maintaining the germplasm of
some improved types.
• World’s largest pear germplasm about 1700 accessions
representing 26 major Pyrus taxa and their hybrids are being
maintained at USDA National Clonal germplasm Repository in
Corvallis, USA.
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15. Blossombiology
• Chilling requirement :- 1200 hrs.
• The flower borne from terminal, mixed buds of short spurs,
appearing before or with the leaves. The spurs are very short
and lateral branches.
• Flower corymbose inflorescences, 5-7.5 cm wide, containing
5-7 showy white, 2.5-3.5 cm wide flower and protogynous.
Each flower has 5-6 petals, 20-30 pink, red or purple anthers
with 2 to 5 free style.
• The ovary is epigynous, or inferior, with the 5-carpellate ovary
embedded in receptacle tissue, containing up to 10 ovules (2 per
carpel); peduncle thin, 2.5-5 cm long.
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16. • According to Farkas and Orosz-Kovacs (2009) stigma in pear
flowers starts to functional 1-4 days before anther dehiscence and
it lost turgidity, collapsed and turned brown 46-98 hrs after
anthesis, depending upon the weather conditions.
• Pears are self-sterile and need more than one variety planted within
12 or 15 m of each other in order to cross-pollinate. Honeybee is
the main pollinator.
• The peak period of anthesis was between 10:00 and 1:00 hr and
pollen dehiscence took place between 12:00 and 4:00 hr.
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17. Stages of pear flower development
Swollen Bud Bud Burst Green Cluster Popcorn stage
Petal FallFull BloomKing BlossomFull White
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18. Dormant spur
Full bloom
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19. Breedingsystem
• Pear cultivars are mainly of three types- self fruitful, self
unfruitful and partially self fruitful.
• Self fruitful cultivars like Beurre Hardy, Flemish Beauty,
Patharnakh are not require pollinizer for fruit set, but other two
group are cross pollinated so, they require pollinizer cultivar for
fruit set.
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20. Breedingobjectives
• Higher yield & Improvement in fruit quality
• Prolonging season of maturity
• Ecological tolerance
• Resistance against diseases like Ganoderma and root rot.
• Compact and efficient plant type
• Overlapping bloom period & compatibility with major
pollinizer cultivars
• Amenability to mechanization
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21. Ideotypes
• Early flowering and regular bearer
• Dwarf and compact plant for HDP planting
• Plant resistance to spring frost
• Resistant to major pests and diseases
• Self fruitful or fruit set less depended on pollinizer
• Fruits have long shelf life
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22. Problemsinbreeding
• It is normally a cross pollinated crop, hence highly heterozygous in
nature.
• Long juvenile phase.
• The phenomenon of vegetative parthenocarpy.
• Excessive fruit drop, susceptible to different biotic and abiotic stress.
• In dwarfing rootstock narrow genetic base for dwarfing character
within the genus Pyrus.
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23. Approachesforcropimprovement
1. Introduction
Important and popular cultivars such as Bartlett, Anjou, Kieffer
are only introductions from Europe and are well acclimatized to
the Northern and Southern Indian hills.
2. Clonal selection
Verona 25, Ferrara and Ravenna are clonal selection from the
Bartlett and recommended for commercial cultivation.
3. Hybridization
The series of Old Home x Farmingdale (OH x F) rootstocks has
been developed by successful rootstock breeding programme of
pear.
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24. 4. Polyploidy
• Generally pear is diploid in nature but sometimes, triploid, tetraploid
and hexaploid cultivars are also found in nature. These polyploidy
cultivars are more vigourus and produce larger size fruits as
compared to the normal diploid one.
• Developed some polyploidy plants from the leaves of diploid pear
cultivar ‘Fertility’ by colchicines treatment.
5. Mutation
• Spontaneous mutation has given red coloured cultivar Starkimson
from Clapp’s Favourite and Red Anjou from Anjou.
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25. Futurethrust
• In India, very little breeding work had been done in the past in
pear. Only some work was done for varietal improvement. But
the region of temperate Himalayan Mountains has wide diversity
of Pyrus and Cydonia. So, it is very important to exploit them
which may be suitable breeding materials in future.
• Rootstock breeding to combine specific traits like higher yield,
improved fruit quality, resistance to different biotic and abiotic
factors along with graft compatibility, is going on in different
pear breeding station around the world. But till now not a single
rootstock is developed to meet the demand worldwide. So,
breeding strategies in these aspects should be taken in the near
future.
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26. Jackfruit breeding
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27. Introduction
• Common name:- Jack tree, Jakfruit, Jack or Jak.
• National fruit of Bangladesh.
• The jackfruit tree is well suited to tropical lowlands, and its fruit is
the largest tree-borne fruit.
• The jackfruit also provides a potential solution to countries facing
problems with food security, such as Africa.
• The jackfruit is a multiple fruit, composed of hundreds to thousands
of individual flowers, and it is the fleshy petals that are eaten.
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28. Scientificclassification
Botanical name:- Artocarpus heterophyllus
Genus: Artocarpus
Subfamily: Asteroideae
Family: Moraceae
Order: Rosales
Basic chromosome No.: 2n=56
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29. Originanddistribution
• It is native to parts of South and Southeast Asia and is believed
to have originated in the south western rain forests of the
Western Ghats in the Indian subcontinent.
• It spread early on to other parts of India, southeast Asia, the
East Indies and ultimately the Philippines.
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30. Species
1. Artocarpus heterophyllus – commercially cultivated species
2. Artocarpus hirsutus (Anjili Chakka) – The Wild Jack Fruit of
kerala
3. A. integrifolia – rarely found in the Pacific
A. heterophyllus A. hirsutus
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31. Cultivars
1. Singapore jack,
2. Konkan Prolofic,
3. Hybrid jack-5,
4. PLR-1,
5. Burliar-1,
6. PPI-1
7. Sindhoora,
8. Pattamuttam,
9. Hazari,
10. Gulabi,
• A 3000 year old Elite jackfruit tree has been located in
Kachahalli village (KN), which is documented under
geographical indication for its excellent fruit qualities.
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32. Cytogenetic
• Artocarpus heterophyllus is a tetraploid and the somatic
chromosome number is (2n) 56 (2n=4x=56), hence the
basic chromosome number (x) is 14.
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33. Geneticresources
• In India, 67 germplasm accessions of jackfruit are conserved at
ICAR-NBPGR Regional Station, Thrissur. Among them 11
accession are characterized for 20 fruit characters.
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34. Blossombiology
• The jackfruit tree is monoecious, having male and female
inflorescences or spike on the same tree.
• Flowering in jackfruit starts in December and continues until
March.
• Male and female inflorescences are borne on footstalks, which
appear on branches or stems initially as yellow-green, bud-like
structure.
• The ratio of male to female inflorescences varies and most of the
studies indicate a higher proportion of male than female
inflorescences.
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35. • The spike can easily be identified when small, because the length
and diameter of female inflorescences are larger than male
inflorescences. Also the surface of a young male spike is smooth,
whereas that of the female is granular.
Male flower
Female flower
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36. • The stamens has four anthers and emits a sweet scent. It splits to
expose a mass of sticky, spherical, yellow pollen grains.
• Female flower are larger, elliptic or rounded, with a tubular calyx.
The flowers are reportedly pollinated by insects and wind.
Individual female flowers are borne on fleshy receptacles.
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37. Breedingsystems
• Jackfruit is an out-crossing species, it freely crosses with A.
integer.
• A. lanceaefolius and A. rigidus are closely linked to A.
heterophyllus whereas, A. nitidus appears to be quite seperate.
• No reports have been found on interspecific crosses involving
these species.
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38. Breedingobjective
• To developed a variety that is regular and prolific in bearing
high quality fruits.
• To enhance the weight of the edible pulp from about 30 to 45
% of the fruit.
• To improve yield, the no. of fruits per tree should be increased
instead of getting a lower no. of bigger sized fruits.
• Reducing juvenile phase.
• Reducing tree height for high density plantings and also for
convenience in cultural operations.
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39. Ideotypes
• Vigorous and prolific plants compatible with one or more
rootstocks.
• Easy manageability and requiring less or no pruning.
• Early flowering and regular bearing.
• Good quality fruit with acceptable pulp colour and texture,
good flavour and sweetness.
• Fruits with symmetrical form and acceptable size.
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40. Approachesforcropimprovement
• Jackfruit has a high nutritive value and a wide range of
uses but it is still recognized as a minor and under-
utilized fruit. As a result, research investment to improve
this crop is very limited and thus breeding strategies have
not been developed for it.
• Whatever varieties are grown commercially, they are all
selection made by enlightened growers based on their own
ideas of suitability.
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41. Currentimprovementefforts
• A major effort has been made to initiate selection by carrying
out standard characterizations and identification of trees with
desirable characteristics. This was done under the auspices of
Underutilized Tropical Fruits in Asia Network (UTFANET).
The efforts was intended to be participatory in association with
farmers.
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