at hiqher temoeratures (Ezekiel, 1997) Field evaluation studies (Garg et et , 1994, ... aftectmq little tuber production (Ezekiel , 1997, SlIlgh,1998) low temperature ...
Potato, r;e1 og
05 -1 og vari c ly'
K.B
KCM
K.S
Mean
K.B
~
KCM
K .S
Me an
KB
KCM
KS . Mean
=-.
-~
- . - =-. . "':::. .
K.B KCM
K.S
T, (2)
186
2 14
147
182
81
80
27
61
5
0
2
2
27
2.9
T2 (3)
301
253
67
207
100
95
44
80
6
2
5
4
4 1
3.5
1.2
T3 (4)
352
363
198
304
120
105
49
91
8
4
0
4
4 .8
4.7
2.5
T, (5)
349
549
38 7
432
157
41
109
7
0
17
8
5.3
6 .8
4.5
T s (6)
6 19
9 13
582
704
234
128 151
42
142
42
18
18
26
9 .0
10.8
6A
Te (7)
48 3
9 16
1049
816
148
117
95
120
9
86
48
6.8
10A
12.3
Average
382
534
405
140
113
50
5.5
6 .5
4 .8
50 20
6
21
18
gibberellins (Railton and Wareing, 1973, Krass and Marschner, 1982) Further absc rsic acid (ABA) and othe r Inhibitors are also known to increase under condi tions of stress such as low temperatu re, desiccat ion, wo und ing (as cause d by desp routmq In our study) ageing and short day conditions (Railton and W arelng,1973 , Krass and Ma rschner, 1982, van Berke l et oi. . 1994) Though growth regulato rs were not estimated In this study , It ap pears tha t growth promoter and Inhibitor ba lance In the ageing mot her tubers might play a role In the Induc tion and productio n of little tube rs The results reported here clearly show low tempera ture promoted Induct ion and production of littie tubers Thrs low temp erature effect migh t be mediat ed through changes In growt h pro mote rs and inhibitors Changes In growt h reg ulato rs and ot her biochem ical para mete rs during the form ation and deve lopm ent of little tubers should be stud ied in deta il in order to understan d the exact mecha nism of little tuber form ation REFERE NCES C.P .R.!. 1996 -9 7 AnlJuai SC/CIJ{ i(,c Reuon, Ce ntral Potato I\ esearcll instuutc Shunla. pp 14- 15 Davi s, H.V. 1996 Recent devel opm ents in
27
O LiI'
knowle dge of pota to transgenic biology PO/Dlo Rese etch 39 4 11
1120
Potato, C;ectd
R~ r:t- Tftv~
Oimalla, G.G. and J . va n Staden. 1977 Effect of ethy lene on the endogenous cytokinin and gibbere llin lev els in tuberi z ing po tatoes Plan t Physiology 60 ' 2 18-2 1. Ewing, E.E . 198 5. Cuttings as sim plified models of potato plant. In Pot at o Ph y sio logy (Ed P.H Li). pp .154 -20 7, A.P . Orlan do . Ewing, E.E. and P.F. Wareing . 19 78 . Sh oot , stolon and tube r forma tion o n po tat o (Solanum tuberosum L.) cutting in respon se to photop eriod Pl ant Phy siology 61 : 348-53 . Ezekiel , R. 1997 . Produ ction of m initub ers on physiologi ca lly old mother tubers of pota to in sto rage. In National sem in ar on p lant ph y siology for sus tainable agric ult ure , ISPP, IARI , New Delhi , March 19- 2 1, pp .20 (Ab str.). Garg , V.K ., S . Singh and T.P . Trivedi . 1994. Field pe rfor mance of mini tub ers produ ced on tube rs of seven pota to cul tivars. In Potato - Pre sent and Fut ure (Eds G.S. Shekhaw at et al.) , pp .318 -20, Indian Potato As sociation, Sh imla . Krass , A . and H. Marschner. 1982. Inf luence of nitrog en , day length and temperature on con tent of gib bere llic and ab sc isic acid and on tub eriz ati on in potato pla nts. Potato Research 25 , 13-21 . La ngille, A.R. 1969 . Effec t of growth reg ulat ors in co ntro lling "litt le tu ber" condition. Canadian J. Plant Scien ce 49 : 800 -02 Ra ilton, 1.0. and P.F . Warei ng. 1973 Effects of day leng th on endogenous gibbere llin in leaves of Sol anum ancJigen a Phvsiotc ai » Pl enierum 28 88 -94 . Singh , S. 1998 . Minitub er production on stored potatoes. A n innovation in seed production and its di men sions. J. tn oien Potato Asso c. 25 : 66-72 . van Berkel, J., F. Salami and C. Gebh art. 1994. T ran sc ripts accumula ting du ring co ld stora ge of potato (Solan um tu beros um L) tubers are seq ue nce related to stress resp on sive ge nes Plant Physio logy 104: 44 5- 52 . van Staden , J . and G.G. Oimalla. 1976. Endogenou s cytokinin and tube rization in the po ta to . An nals Bo tany 40 . 11 17- 19. van Staden , J . and G.G . Oimalla. 1977. The dist ribut ion of cyto kiruns in tuberizing pota toes . Annals Botany 41 : 74 1 46.
