Chapter 3 Comparison of performance of lucerne varieties under irrigated and
4.3 Results
4.3.2 Effect of mulching on yield and its components
Shoot height (cm): In the present study, shoot height of lucerne varied from 18- 78 cm.
Interactions among treatments and years were found non-significant. Differences among treatments were found non-significant for SH. Differences among years were significant (P < 0.01) for SH. In 2007, SH for lucerne mulch (M) was 24.7 cm as compared to SH of 18 cm for no mulch (NM). In 2008, SH for both treatments was similar (78 cm).
Shoot number (m-2): Shoot number varied from 506-720 m-2. Interactions among treatments and years were found non-significant. Differences among treatments were found non-significant for SN. Differences among years were significant (P < 0.05) for SN. In 2007, SN for M was higher (720m-2) as compared to NM (693 m-2). In 2008, SN for NM was higher (581 m-2) as compared to M (506 m-2).
Leaf area index: In the present study, LAI varied from 0.5-2.6. Interactions among treatments and years were found non-significant. LAI was not significantly affected due to treatments. Differences in LAI were found significant (P < 0.01) among years. In 2007, LAI was 0.52 for NM and 0.75 for M while in 2008, LAI was 2.6 for NM and 2.2 for M (Table 23).
Chlorophyll content: Chlorophyll content varied from 458-642 mg m-2 of leaves.
Interactions among years and treatments were found non-significant. Chlorophyll content was not significantly affected due to treatments. Years had significant (P < 0.01) effect on chlorophyll content. In 2007, chlorophyll content was 493 mg m-2 of leaves and 458 mg m-2 of leaves while in 2008; it was 585 mg m-2 of leaves and 642 mg m-2 of leaves for NM and M, respectively.
Shoot dry matter yield: Shoot dry matter yield (SDMY) ranged from 855-3665 kg ha-1. Interactions among treatments and years were found non-significant. Differences among treatments were found non-significant for SDMY. Years differed significantly (P < 0.01) on SDMY. In 2007, SDMY was 855 and 983 kg ha-1 while in 2008 SDMY was 3184 and
3665 kg ha-1 for NM and M, respectively (Fig. 4.1). Lower SDMY in 2007 can be attributed to yearly effect and damage by rats and rabbits.
Table 4.4: Summary of results on yield and its components
Parameter Treatment Year Treatment x Year
Shoot height (cm) ns * ns
Shoot number (m-2) ns ** ns
Leaf area index ns * ns
Chlorophyll content ns * ns
Shoot dry matter yield (kg ha-1) ns * ns
Root dry matter yield (kg ha-1), 0-60 cm ns * ns
Total dry matter yield (kg ha-1) ns * ns
Total N yield ( kg ha-1) ns * ns
Total Ndfa (%) ns * ns
Biological nitrogen fixation (kg ha-1) ns * ns
Actual Evapotranspiration (mm) + * ns
ns- non- significant, *- significant at 1 % level of probability, **- significant at 5 % level of probability
+- significant at 10 % level of probability
0 500 1000 1500 2000 2500 3000 3500 4000 4500
2007 2008
Year Shoot dry matter yield ( kg ha-1) No mulch Mulch
Error bars indicate one standard deviation. Different capital and small letters indicate significant differences among years and treatments, respectively.
Figure 4.1: Shoot dry matter yield at second harvest under different lucerne utilization systems.
Root dry matter yield: RDMY ranged from 5526-11823 kg ha-1 in 0-60 cm of soil profile in the present study. Interactions among years and treatments were found non- significant. Effect of treatments was found non-significant on RDMY. Years differed significantly (P < 0.01) for RDMY. In 2008, RDMY in 0-60 cm of soil profile was
Ba Ba
Aa Aa
10830-11823 kg ha-1 as compared to RDMY of 5526-6370 kg ha-1 in 2007. RDMY in 0- 60 cm of soil profile under different lucerne utilization systems in both years of experiments is shown in figure 4.2.
0 2000 4000 6000 8000 10000 12000 14000 16000
2007 2008
Year Root dry matter yield (kg ha-1 ) No mulch Mulch
Aa
Ba Ba
Aa
Error bars indicate one standard deviation. Different capital and small letters indicate significant differences among years and treatments, respectively.
Figure 4.2: Root dry matter yield at second harvest under different lucerne utilization systems.
Total dry matter yield: In the present study, TDMY ranged from 7260-16095 kg ha-1. Interactions among treatments and years were found non-significant. Treatments did not differ significantly in producing TDMY. TDMY differed significantly (P < 0.01) among years. In 2007, TDMY was 7260-8030 kg ha-1 while in 2008 TDMY was 10830-11823 kg ha-1. TDMY under different lucerne utilization in both years of experimentation is shown in figure 4.3.
Biological nitrogen fixation: Interactions among treatments and years were found non- significant for total N yield and Ndfa %. Treatments also did not differ significantly for total N yield and Ndfa %. Significant (P < 0.01) differences were observed among years for both total N yield and Ndfa % (Table 4.4). In 2007, N yield was 340 kg ha-1 and 387 kg ha-1, for M and NM, respectively. In 2008, N yield was 686 kg ha-1and 724 kg ha-1 for M and NM, respectively. In 2007, Ndfa under M was 46.75 % as compared to 47.25 % under NM. In 2008, Ndfa under M was 57.75 % as compared to 62.5 % under NM.
0 5000 10000 15000 20000 25000
2007 2008
Year Total dry matter yield (kg ha-1) No mulch Mulch
Aa
Ba Ba
Aa
Error bars indicate one standard deviation. Different capital and small letters indicate significant differences among years and treatments, respectively.
Figure 4.3: Total dry matter yield at second harvest under different lucerne utilization systems.
Interactions among treatments and years were found non-significant for BNF. Treatments did not differ significantly in BNF. Years had significant (P < 0.01) effect on BNF. In year 2008, the amount of total BNF was more than two times as high as in 2007 (see figure 4.4).
0 100 200 300 400 500 600 700
2007 2008
Year Biological nitrogen fixation (kg ha-1)
No mulch Mulch
Ba B
a
Aa Aa
Error bars indicate one standard deviation
Figure 4.4: Total biological nitrogen fixation under different lucerne utilization systems.
A summary of statistical analysis of results is shown in Table 4.4. Data on yield and its components under different lucerne utilization system are presented in Table 23 (see Annexure-1).