Clonal variation in temperature response of photosynthesis in tea
Introduction
Tea (Camellia sinensis (L.) O. Kuntze) is a small tree but the plants are maintained in the form of bushes by continuous pruning. It is an important plantation crop of India and is grown in various agro-climatic zones. India is a major producer of tea both for the domestic and world market. The ever increasing demand for tea can be achieved, to a certain extent, by increasing the area under tea; a better option would be the use of high yielding clones and by growing clones most suitable for specific climatic regions.
Temperature is one of the major environmental factors determining the rate of growth and the natural geographic distribution of tea [1]. It has been demonstrated that temperatures above 30 and below 13°C are not conducive for the growth of tea bush [2]. Many high yielding tea clones are being used under tea plantation programmes in the Central Himalayan region which show considerable seasonal and diurnal variation in temperature. Therefore, the success in terms of yield would depend on the proper selection of clones which are better suited to the prevailing climatic conditions.
Photosynthesis, being one of the first physiological processes to be greatly affected by temperature [3]is widely used as a tool for indicating temperature stress [4]and for the rapid selection of plants most suitable for different habitats [5]. Existence of a close relationship between photosynthetic rates and yield in several plant species has also led many workers to use photosynthetic characteristics as criteria for selection of high yielding clones 6, 7. In the case of tea, with some exceptions 8, 9, studies have shown that the growth of the harvestable shoots (yield) depends on the photosynthetic rate of maintenance leaves and developing shoots 10, 11. Thus any existing variation in the photosynthesis may offer a greater potential for yield improvement in tea. Further, in many plant species genotypic and/or clonal variations in photosynthetic characteristics and yield in relation to temperature have been reported 6, 12. However, such information is lacking for tea clones [13]and therefore, the present investigation was undertaken to determine the clonal variation, if any, in photosynthesis in relation to temperature.
Section snippets
Plant material
Approximately 3 year old and cutting raised plants of six tea clones namely; (i) B/6/62-UPASI 10: a China hybrid quality clone selected at Brooklyn Tea Estate, Nilgiri Hills, South India; (ii) CCS-26: a China hybrid from Banuri Tea Experimental Farm, Kangra Valley, Himachal Pradesh; (iii) 6017-Craigmore: a China hybrid clone selected in South India; (iv) B/5/63-UPASI 3 or Sundaram: an Assam hybrid, triploid clone selected at Brooklyn Tea Estate, Nilgiri Hills, South India; (v) B/6/61-UPASI 9 or
Results
Fig. 1 shows the temperature dependent photosynthetic curves for six tea clones at the saturating light intensity. It is evident from this figure that tea clones differ greatly in their photosynthetic response to temperature variation. Both the optimum temperature and temperature range over which net photosynthesis occurred varied with clones. Maximum photosynthesis was observed at 25°C in clones 6017, B/6/62, CCS-26 and T-78 and at 30°C in clones B/5/63 and B/6/61. Clone CCS-26, however,
Discussion
Genotypic and or clonal variations in photosynthetic characteristics and yield in relation to temperature have been reported in several plant species 6, 12. Though there are some studies on the temperature requirement of the tea plant for net photosynthesis and productivity 11, 13, 16, 17, 18, but to the best of our knowledge this is the first report in which clonal variations in photosynthetic characteristics have been investigated in relation to temperature. The photosynthetic temperature
Acknowledgements
Many thanks to Dr M.B. Tamang (C.S.I.R. Complex, Palampur, H.P.) for providing tea plants of various clones used in this investigation. This study forms a part of a Department of Biotechnology, Government of India supported programme on Himalayan tree species including tea.
References (29)
- et al.
Relation between photosynthesis and dark respiration in cereal leaves
J. Plant Physiol.
(1996) - G.R. Squire, B.A. Callander, Tea plantations, in: T.T. Kozlowski (Ed.), Water Deficits and Plant Growth, Vol. VI,...
- D.N. Barua, Science and Practice in Tea Culture, Tea Research Association Calcutta, 1989, pp....
- et al.
Photosynthetic response and adaptation to temperature in higher plants
Ann. Rev. Plant Physiol.
(1980) - W. Larcher, Photosynthesis as a tool for indicating temperature stress events, in: E.-D. Schulze, M.M. Caldwell (Eds.),...
- et al.
Seasonal changes in photochemical efficiency and leaf area of nitrogen and non-nitrogen-fixing tree species grown in degraded land
J. Sustainable Forestry
(1996) - et al.
Genetic variation in photosynthetic traits among Populus clones in relation to yield
Plant Physiol. Biochem.
(1988) The close relationship between net photosynthesis and crop yield
Bioscience
(1982)Seasonal changes in photosynthesis of tea (Camellia sinensis L.)
J. Appl. Ecol.
(1977)Some factors limiting yields of tea (Camellia sinensis L.)
Expl. Agric.
(1979)
Photosynthesis in tea.I. Contribution of photosynthates to pluckable shoots by maintenance leaves
Two and a Bud
Photosynthesis and productive structure of mature tea (Camellia sinensis L.) bush during growth of the first flush
Jpn. J. Crop Sci.
Genotypic variation in chlorophyll fluorescence parameters, photosynthesis and growth of tomato grown at low temperature and low irradiance
Photosynthetica
Effects of clone and irrigation on the stomatal conductance and photosynthetic rate of tea (Camellia sinensis)
Expl. Agric.
Cited by (24)
Light dependence of photosynthesis and water vapor exchange characteristics in different high δ<sup>9</sup>-THC yielding varieties of Cannabis sativa L.
2015, Journal of Applied Research on Medicinal and Aromatic PlantsCitation Excerpt :However, C. sativa is an extremely variable species in terms of morphology, eco-physiology and chemical contents due to its allogamous nature (ElSohly and Slade, 2005; Upton et al., 2013). In many plants species, genotypic and/or clonal variations in photosynthetic characteristics and yield in relation to variable environmental factors have been well reported (Isebrands et al., 1988; Janssen et al., 1995; Joshi and Palni, 1998). Such information, despite of its high medicinal and economical values, is completely lacking for C. sativa varieties/clones.
Sub-regional variation in atmospheric and land variables regulates tea yield in the Dooars region of West Bengal, India
2023, International Journal of BiometeorologyImpact of climate on tea production: a study of the Dooars region in India
2022, Theoretical and Applied ClimatologyGlobal climate change, ecological stress, and tea production
2018, Stress Physiology of Tea in the Face of Climate ChangeAlterations in growth, photosynthetic activity and tissue-water relations of tea clones in response to different soil moisture content
2017, Trees - Structure and Function