Question

Describes about tomato plant biochemical pathway or physiological process related to plant water use efficiency, (ii) shows an analysis of the critical components that regulate this pathway or process and (iii) presents one original opinion or suggestion on the improvement of plant water use efficiency.

Answer 1

1. An experiment conducted in a tomato plant gives the following conclusions by dividing its entire life span into 5 stages:

• Vegetative growth stage (VG)
• flowering and fruit setting stage (FS)
• early fruit growth stage(FG)
• fruit development stage (FD)
• fruit maturity stage(FM)

It is very important to supply plants with an adequate amount of water and fertilizers in different stages of its growth to result an improved yield with high water use efficiency. To understand the tomato plant biochemical pathway or physiological process related to plant water use efficiency we can moisture and fertilizer the tomato plant in different water levels and potassium (K) fertilization. Water levels include W1, W2, and W3 indication that soil water was maintained at 60- 70% field capacity, 70- 80% field capacity, and 80- 90% field capacity. K level includes K1, K2, and K3 indicates 0 g K2O per kg soil, 0.42 g K2O per kg soil, and 0.92 g per kg soil was applied. All combinations of water and K fertilizer is applied in the different stages of the growth and in other hand plant were watered to 80- 90% field capacity without K fertilizer (W3K1). The permanent W3K1 over the entire growth stage was taken as control. The result showed that the water deficiency imposed at all stages significantly affected tomato yield except for vegetative growth stage (VG) in which water deficiency did not cause any yield loss. K fertilization during FS or FM stage had a great significant on yield. A significant interaction effect of water and potassium fertilizer on yield was only observed during FM stage. For water use efficiency significant effect of water deficiency at FS, FD and FM stages were observed. During FS stage sufficient water supply seems necessary, a deficit irrigation with K fertilizer could be applied as K fertilization could alleviate the negative effect of soil water deficit, however excessive amount of K fertilization during FM stage should be avoided to maintain tomato yield and water use efficiency.

2.

FACTOR	SUM OF SQUARE	DEGREE OF FREEDOM	MEAN SQUARE	F- VALUE	P- VALUE
K vs W1	0.041	2	0.020	5.334	0.015*
K vs W2	0.098	2	0.042	12.907	0.000*
K vs W3	0.123	2	0.062	16.204	0.000*
W vs K1	0.372	2	0.186	48.937	0.000*
W vs K2	0.242	2	0.121	31.816	0.000*
W vs K3	0.081	2	0,040	10.630	0.001*

NOTE: W1, W2, W3 indicated three different levels of moisture and K1, K2, K3 indicated Potassium levels

* indicates a significant effect (P<0.005)

*indicates a highly significant effect (P<0.001)

3. Crop genetics is an effective suggestion for the improvement of plant water use efficiency. This approaches to raising water use efficiency through the selection of varieties with growth characteristics and tolerance matched to relatively location specific conditions.