Grafting is a centuries old technique used to unite two different plants of same specie or of different species for desirable traits. In fruits grafting is very old technique but in vegetables it is comparatively new. The oldest record of grafting vegetable plants is in 500 AD in China, when farmers joined together multiple gourd plants to develop a greater root system to increase the size of gourd fruit that were used for rice storage during the winter season. Now a day, it is used in many countries which include Spain, Germany, Turkey, America, Canada and Mexico. Commercial production and demand for vegetable grafted plants continuous to increase in Asia and Europe. It is an environment friendly technique use to control soil borne diseases, to induce resistance or tolerance against abiotic and biotic stresses to increasing the yield of susceptible cultivars. It is currently used for different vegetable such as watermelon, melon, cucumber, pepper, tomato and eggplant. Many countries utilize vegetable grafting and get better yield from limited land.
By Bilal Akram and Dr. Muhammad Azher Nawaz (Horticulture, UOS)
is an overview of different factors that are directly supported by use of
vegetable grafting technique and these factors are of great importance for
Pakistan. Water is becoming an increasingly scarce resource in many parts of
the world including Pakistan. The competition among industrial and agricultural
use of water creates the need for improving irrigation practices. By use of
grafted transplants we can minimize the need of water by selecting a drought
tolerance rootstock. There are evidences of improving the drought tolerance of
plants by use of vegetable grafting such as grafting of tomato on eggplant
helps to survive transplants under drought stress conditions due to its strong
roots system compared with tomato. Grafted transplants help plants survive under
water logged conditions but also increase the chlorophyll content in the leaves.
Grafting improve flooding tolerance of bitter gourd when grafted onto lufa. We
can save a plenty of water by use of vegetable grafting technique.
land is speedily converted in to barren land due to salt accumulation. Every
year thousands of acre land became useless because of high rate of salts. As
salinity is a big threat to agricultural and there is no effective system to
reclaim these types of degraded lands and we have to live with them. Using salt
tolerance and vigorous rootstock we can use salt effected lands for growing
vegetables. Wild types of rootstocks for different vegetables are tolerant to
salt to some extent.
Yield of vegetables (tons/hectare) in
Nawaz et al., 2017)
Pakistan farmers are facing shortage of quality fertilizers and government also
fails to facilitate them. Increase in the price of fertilizer is a big issue for
farmer. Farmers are not applying the fertilizers according to recommendation
due to their high prices. By use of vegetable grafting we can save more than
50% of the fertilizers without compromising yield. By using vigorous rootstocks
the frequency of agrochemical application can be significantly reduced. In
watermelons, the amount of chemical fertilizers can be reduced to about
one-half to two-third compared with the standard recommendation for the
uptake can also improve by grafting. Drought tolerance provided by either
rootstock or scion improves nitrogen fixation in soybean. Grafting also
improves the absorption and translocation of nitrogen, magnesium, phosphorous,
and calcium and several other essential nutrients. Improved nutrient uptake in
grafted transplants also increases photosynthesis under unsuitable climatic
conditions such as weak sun light and low level of CO2.
most dangerous threat to agriculture sector is changing environmental
conditions like very low and very high temperature. Growing seasons as well as growth habit of plants is
badly affected due to sudden change in temperature. In
grafting we use rootstock which is normally temperature hardy, may help to
compete with rapidly changing temperature. To reduce resistance against low or
high temperature grafting is used. Grafting not only makes plants resistant to
survive under extreme temperature but also increases the yield. Figleaf gourd
rootstock has been used commercially for water melon, cucumber and melons to
increase tolerance to low soil temperature. Grafting helps plants to survive
under low temperature due to presence of more Linolenic Acid. Pepper had a
higher yield under high temperature when grafted onto sweet pepper rootstock.
grafting is proved as a shield against heavy metals. Grafted plants survive
effectively under heavy metal stress compared with non-grafted plants under
same environmental conditions. Grafting minimize the negative effect of copper,
cadmium, vanadium, and manganese toxicity.
vegetable grafting we can control diseases attack on crops by using resistant
rootstock. The disease tolerance in grafting seedlings may be entirely due to
tolerance of rootstock to the diseases. Soil borne fungal diseases can be
effectively controlled by using vigorous rootstocks.
has a direct effect on yield of crop. By using selected, compatible and
vigorous rootstock we can get maximum marketable yield. In oriental melons,
increases of 25-50% yield have been reported by using grafted plants. There is
also evidence of increased yield in tomato by 54%. In other vegetables such as cucumber,
chili, eggplant and watermelon yield was increase by up to 8.80-57%, 9.20%,
27.70% and 22.7-43%, respectively by using grafted transplants.
is an effective approach to improve fruit quality under both optimum growth
conditions and salinity. Grafted plants have higher marketable yield, fruit
quality and sugar content of fruits depending on rootstocks. Total phenolic
contents increased in grafted eggplants compared with non-grafted plants.
Why vegetable grafting in Pakistan?
Pakistan is not an economically
strong state; our resources are decreasing with time. By using vegetable
grafting technique minimize the impact of shortage of water, land and
fertilizers and can also handle changing environmental conditions. Agriculture department, public universities,
private universities and private sector have to work on vegetable grafting to
make it useable for local farmers and to provide them with quality transplants
to move towards precision agriculture.
There is a need of vegetable
grafting in Pakistan to boost production of vegetable and to take it at the
level of other countries to full fill the increasing demand of vegetables. By
the use of grafted transplants the use of pesticides is minimized thus it
promotes organic vegetable production.
limitations/ constraints in adopting vegetable grafting in Pakistan
are several limitations in successful utilization of vegetable grafting
technique in Pakistan that includes
- Lack of awareness among farmers
- Lack of interest of public sector
- Lack of funds for research and development
- Uncharacterized germplasm for rootstock and scion cultivars
- Unavailability of proper infrastructure (green house, germination
and healing chambers)
- Enhanced utilization of seeds for the preparation of grafted
- Lack of trained labor/staff
- Expected high price of grafted transplants
M.A., F. Shireen, Y. Huang, B. Zhilong, W. Ahmed and B.A. Saleem, 2017.
Perspectives of vegetable grafting in Pakistan: current status, challenges and
opportunities. International Journal
of Agriculture and Biology, 19: 1165‒1174