wire attached to a door-bell buzzer) was used to vibrate flowers at a high frequency, which released the pollen and saturated the stigmatic surface. Flowers were ...
Oecologia (1990) 84: 82-92
Oecologia
9 Springer-Verlag 1990
Role of mycorrhizal infection in the growth and reproduction of wild vs. cultivated plants II. Eight wild accessions and two cultivars of Lycopersicon esculentum Mill. David R. Bryla* and Roger T. Koide Department of Biologyand Program in Ecology,The PennsylvaniaState University,UniversityPark, PA 16802, USA Received January 2, 1990 / Accepted in revised form March 12, 1990
Summary. An experiment was conducted to determine whether wild accessions and cultivars of Lycopersicon esculentum Mill. differed in inherent morphological, physiological or phenological traits and whether such differences would result in variation in response to vesicular-arbuscular mycorrhizal infection. While distinctions between wild accessions and cultivars were apparent (the cultivars generally had higher phosphorus use efficiencies and shorter lifespans than the wild accessions) and the cultivars were, as a group, more responsive to mycorrhizal infection than the wild accessions, there was significant variation among wild accessions and among cultivars in response to infection. Regardless of cultivation status, non-mycorrhizal plant root density was significantly negatively correlated with response to infection. Phosphorus use efficiency was generally not significantly correlated with response to infection. Mycorrhizal infection decreased phosphorus use efficiency in all accessions, but had variable effects on root density, depending upon accession and time. Finally, the vegetative response was not necessarily of the same magnitude as the reproductive response. Key words: Vesicular-arbuscular mycorrhiza -
Lycopersicon esculentum - Mycorrhizal dependency - Adapta-
tion to infertility - Mineral nutrition
The great majority of terrestrial plant species form symbioses with vesicular-arbuscular mycorrhizal fungi. These fungi have been shown to affect both nutrient uptake and allocation (Koide etal. 1988; Koide and Lewis unpublished). The study of this symbiosis, therefore, is essential for a complete understanding of plant nutrient acquisition and utilization in most plant communities. One important aspect of mycorrhizal nutrient relations is variation among plants in their response to Offprint requests to: R.T. Koide *Current address. Department of Plant Pathology University of California Davis, CA 95616 USA
mycorrhizal infection (Koide et al. 1988). Variation in response to infection may affect plant community structure (Janos 1980) by differentially influencing competitive ability or reproduction. Chapin (1980) and Chapin, Vitousek and Van Cleve (1986) have shown that wild plants possessed of adaptations for growth in nutrient-poor soils are often less responsive to nutrient inputs than cultivated species. This suggested that differential adaptation to soil infertility in wild vs. cultivated species might lead to variation in responsiveness to mycorrhizal infection (Koide et al. 1988). Variation in the response of different plant species to vesicular-arbuscular mycorrhizal infection is well documented (Crush 1974, Mosse 1978, Lambert and Cole 1980, Plenchette et al. 1983a, 1983b, Saif 1987, Koide et al. 1988). Differential response to mycorrhizal infection has also been demonstrated among cultivars of corn (Hall 1978), soybean (Skipper and Smith 1979), wheat (Azcon and Ocampo 1981), pearl millet (Krishna et al. 1985), pea (Estaun et al. 1987) and cowpea (Rajapakse and Miller 1987, 1988). Although infection by vesicular-arbuscular mycorrhizal fungi may have effects independent of phosphorus nutrition (Sylvia 1986; Edriss et al. 1984), the most pronounced effect is generally on the plant's phosphorus economy. It is reasonable to expect, therefore, that the response to mycorrhizal infection should be related to a plant's inherent ability to respond to phosphorus input (Hayman 1983, Plenchette et al. 1983a, 1983 b, Lioi and Giovannetti 1987). Graham and Syvertsen (1985), for example, found that citrus rootstocks which were less able to respond to additions of phosphorus were also less responsive to mycorrhizal infection than those which were more able to respond to additions of phosphorus. Response to infection may thus be related to the phosphorus use efficiency (defined as the amount of biomass per unit of phosphorus, see Chapin, 1980) for growth or reproduction because it reflects how responsive a plant is (in accumulation of biomass) for a given increase in phosphorus content. If phosphorus use efficiency were high, a given increase in phosphorus absorption due to
83 mycorrhizal infection would have a greater effect on growth than if phosphorus use efficiency were low. Indeed, phosphorus use efficiency has been shown to be positively correlated with responsiveness to mycorrhizal infection ( G r a h a m and Syvertsen 1985; Menge et al. 1978). The ability to respond to phosphorus inputs should also be a function of inherent capacity to acquire phosphorus, which, in turn, m a y be a function of root m o r phology. Several researchers have related the responsiveness of a plant species to mycorrhizal infection to inherent traits such as root length, root weight, root density, root fineness or root: shoot ratio (Menge et al. 1978; H a y m a n 1983; G r a h a m and Syvertsen 1985; Hetrick et al. 1988; Koide et al. 1988). Those species which have a higher degree of root development appear to benefit less from infection than those which have a lower degree of root development. Baylis (1975) hypothesized that root hair development is negatively correlated with response to mycorrhizal infection and m a n y reports support this. The tropical grasses Paspalum and Brachiaria, however, appear to contradict this hypothesis. Although they apparently possess extremely hairy roots, they are still very responsive to mycorrhizal infection ( H a y m a n 1983). Moreover, Hall (1975) indicated that Metrosideros is only poorly responsive to mycorrhizal infection despite having very few short root hairs. Thus, it would appear that r o o t characters alone are not always predictive of response to mycorrhizal infection. Metrosideros, despite having a p o o r inherent ability to acquire phosphorus, is also an extremely slow growing species which has a very p o o r ability to respond to increased phosphorus supply and thus would not be expected to benefit greatly from mycorrhizal infection. McGonigle and Fitter (1988) have further suggested that a plant's response to mycorrhizal infection m a y depend on its d e m a n d for phosphorus. For example, response to infection m a y be more positive during a particularly nutrient demanding period such as flowering. I f total phosphorus content for m a x i m u m growth were equal, those plants with shorter lifespans, on average, would require higher rates of nutirent absorption to supp o r t m a x i m u m growth or reproduction. All else being equal, short-lived plants might therefore be more positively responsive to mycorrhizal infection than those with longer lifespans. I m p r o v e d reproductive output is often assumed to be a function of increased primary productivity (Bloom et al. 1985) such that larger plants with more resources produce m o r e flowers and seeds than smaller plants (Rathcke and Lacey 1985; Bazzaz et al. 1987). However, the degree of i m p r o v e m e n t of vegetative growth due to mycorrhizal infection m a y not be a perfect predictor of the degree of i m p r o v e m e n t in reproduction. For example, although mycorrhizal and nonmycorrhizal pepper plants had similar dry weights, mycorrhizal plants produced significantly m o r e flower buds (Dodd et al. 1983). Those plants which more efficiently reallocate nutrients f r o m non-essential vegetative structures to reproductive structures m a y depend less on nutrient acquisition from soil for reproduction than for vegetative growth (Chapin 1980) and m a y therefore be less dependent on mycorrhizal infection for reproduction.
The effects Of mycorrhizal infection on vegetative growth and reproduction of wild and cultivated Lycopersicon esculentum accessions were studied. In a previous study of Arena spp., a comparison was made between one cultivar and one wild species. In the current study, m o r e accessions were investigated in order to determine whether suites of adaptations are generally associated with being either wild or cultivated, or whether traits related to nutrient acquisition and use are independent of wild/cultivated status. Three other questions were also addressed: 1) Do either vegetative or reproductive responses to mycorrhizal infection vary a m o n g accessions ? 2) Can root morphology, phosphorus use efficiency or lifespan be used to predict the relative response to mycorrhizal infection? 3) Does mycorrhizal infection enhance vegetative growth and reproduction to the same extent?
Materials
and methods
Two tomato (Lycopersicon esculentum) cultivars ("Pixie" hybrid and a large cherry) and eight wild tomato (Lycopersiconesculentum var. cerasiforme) accessions (LA1314 - Granja Pichari, Cuzsco, Peru; LA1468 - Cali, Columbia ; LA1709 - Desvio Yojoa, Honduras; LA1205 - Copan, Honduras; LA1228 - Macas, San Jacinto de los Monos, Morona-Santiago, Ecuador; LA1203 - Ciudad Vieja, Guatemala; LA1204- Quetzaltenango, Guatemala; LA1458 - Huachinango, Pueblo, Mexico) were used in these experiments. For convenience, wild accessions will be referred to as Accessions 1 through 8, respectively, and cultivars will be referred to as Accesions 9 (Pixie) and 10 (large cherry). Wild tomato seeds were obtained from the Tomato Stock Center of the Department of Vegetable Crops at the University of California, Davis, CA, USA. The Pixie (determinate) and large cherry (indeterminate) cultivars were obtained from WA Burpee Co., PA, USA and American Seed Corp., MI, USA, respectively. The soil used was a Hagerstown silty-clay loam which had a bicarbonate-extractable phosphorus concentration of 2.9 gg Pg-l, a water pH of 5.8, an organic matter content of 2.7%, a bulk density of 1.25 g cm -3, and a Mehlich III manganese concentration of 115 mg din- 3. It was collected at the Rock Springs Agricultural Experiment Station of The Pennsylvania State University in Centre County, PA, USA. The soil was mixed with sand (1:1 v/v) to increase drainage. Indigenous mycorrhizal fungi were destroyed by autoclaving dry soil for 90 minuts at 121~ C, The soil was stored at least two weeks before planting to reduce the potentially phytotoxic effects of heating (Rovira and Bowen 1966). Seeds of wild tomato were soaked in 2.7 % sodium hypochlorite for 30 minutes and rinsed thoroughly in distilled water before sowing. All seeds were germinated in flats containing vermiculite. Wild and cultivated seeds were sown 13 August and 18 August 1988, respectively, to obtain similar emergence times. The flats were irrigated daily and kept in a growth chamber. On 24 August, two uniform seedlings were transplanted, either with or without mycorrhizal propagules, into each round pot (15.2 cm diameter) filled with 2.0 kg (air-dry) of the soil mix. Approximately 3600 washed spores of Glomus etunicatum Becker and Gerd. (Native Plants, Inc., Salt Lake City, UT, USA), isolated from a sand-based inoculum, were pipetted in 5 ml of water onto the roots of each plant an~t into the soil immediately surrounding the roots. Spore washings (5 ml) were pipetted onto the roots and surrounding soil of control plants. This was done to insure comparable non-mycorrhizal microbial inputs (Koide and Li 1989). Each pot was thinned to one plant on 6 September. In all, 100 plants (10 accessions x 2 inoculation treatments • 5 replicates) were grown. After transplanting to soil, plants were arranged in a Latinsquare design in a ventilated glasshouse with supplemental light provided by four t000-W high pressure sodium lamps. The mean
84 daily total quantum flux density (400-700 nm) under the lamps was 19.4 tool m -2 day-1 and the mean daily maximum instantaneous quantum flux was 1070 gmol m -a sec 1. These measurements were made using the Li-Cor (Lincoln, Nebraska, USA) LI1000 data logger. The mean maximum and minimum air temperatures in the glasshouse during the course of the experiment were 26 and 21 ~ C, respectively. Pots were watered every morning with automatic drip irrigators. In addition, each pot was amended five times weekly with 50 ml nutrient solution. The nutrient solution consisted of one-fifth strength Hoagland solution lacking phosphorus (Machlis and Torrey 1956) containing i mM Ca(NO3)2, 1 mM KNO3, 0.4mM MgSO~, 17.9 gM Fe as FeEDTA, 11.2gM C1, 4.6 gM B, 0.9 gM Mn, 0.46 laM Zn, 0.094 gM Cu and 0.009 gM Mo. Leaf lengths and widths were measured to the nearest 0.1 cm, 2, 3, 4, 6 and 8 weeks after transplanting. Subsamples of leaves (50 per accession) were used at harvest to develop relationships between length (1) x width (w) and true leaf area using the Delta-T (Cambridge, England) leaf area meter. Leaf areas (A, in cm 2) were estimated using the following equation: A = C x 1x w where C is the coefficient of the relationship between length and width and actual leaf area. The coefficients were 0.28 (r2=0.97), 0.31 (r 2= 0.95), 0.36 (r2=0.97), 0.32 (r2=0.98), 0.35 (r2=0.91), 0.30 (r 2 = 0.96), 0.34 (r2=0.97), 0.34 (r2=0.96), 0.44 (r2=0.95) and 0.35 (r2=0.96) for LA1203, LA1204, LA1205, LA1228, LA1314, LA1458, LA1468, LA1709, Pixie and the large cherry cultivar, respectively. Thirty-five days after transplanting, a no. 15 cork bore was used to remove soil samples from each of the 100 pots, midway between the stem and the pot edge. Autoclaved soil was used to replace the soil taken in the core. Roots were washed free and initially preserved in formaldehyde/acetic acid/ethanol (FAA) solution, then stained and examined for length and mycorrhizal infection using a grid intercept technique as in Koide and Mooney (1987). Total pot root length was estimated from the ratios of core volumes to pot volumes as in Koide (1985). Root densities were calculated by dividing root length by soil volume. All accessions and cultivars are self-compatible and exhibit infrequent cross-pollination in the field (Rick, personal communication). At anthesis, flowers were self-pollinated using a Potato Pollinator device (Centre Hall, PA, USA). The pollinator device (a wire attached to a door-bell buzzer) was used to vibrate flowers at a high frequency, which released the pollen and saturated the stigmatic surface. Flowers were then tagged and their date of pollination was recorded. Senesced leaves were collected weekly. Individual plants were harvested when all fruits ripened. Seeds were assumed to be mature when the fruits turned red. At harvest the number of fruits were counted. Duration of fruit set was calculated as the number of days from the initiation of anthesis until fruit set was complete. The vegetative duration was calculated as the time from transplanting until anthesis. Shoots were cut off at the surface of the soil and separated into vegetative shoot (stem, leaves, senesced leaves and pedicels), fruit, and seed components. Seeds were removed from the fruit, fermented for several days, rinsed with distilled water, and air-dried. Seeds were counted and weighed for each fruit. A no. 15 cork bore was used to remove a soil core for the measurements of root length, root density, and mycorrhizal infection, taking care to remove soil from a location different from that previously used for soil sampling. Vegetative shoots and fruits (not including the seeds) were oven-dried at 70~ C for at least 48 h and weighed. Vegetative shoots (without senesced leaves) and fruits were ground and subsamples were digested in a H2SO4/H202 mixture using a Technicon (Tarrytown, NY, USA) block digester. The digestion mixture was then analyzed for phosphorus and nitrogen using colorimetric techniques. For phosphorus, the molybdo-phosphate method (Watanabe and Olsen 1965) was used. For nitrogen, the Nessler's method was used (Jensen 1962). Reference material was included with every 40 samples to check digestion and analytical procedures. Subsampies of seeds (air-dry) from each plant were also analyzed for nutrient concentration.
Vegetative and reproductive responses to mycorrhizal infection were calculated using the following formula: (Dry weight M plant) - (Mean dry weight NM plants) (Mean dry weight NM plants) where M and NM stand for mycorrhizal and non-mycorrhizal, respectively. Total vegetative shoot dry weight, total fruit dry weight per plant and total seed dry weight per plant were used to calculate vegetative and reproductive responses to mycorrhizal infection. Data were analyzed using the multiple-factor analysis of variance and simple regression procedures of the Statgraphics programs (STSC 1987). For all measured characteristics except leaf area, the two factors in the analysis of variance were accession (10 levels) and inoculation treatment (2 levels). For the time course of leaf area, a three-factor analysis of variance was run using time (5 levels), accession (10 levels) and inoculation treatment (2 levels) as factors. Mean separations were accomplished using Least Significant Difference intervals (for 2-way comparisons) or Confidence intervals (for multiple comparisons) of the Statgraphics system (STSC 1987). Single degree of freedom orthogonal contrasts (comparing all wild accessions with the cultivars) were performed according to procedures in Sokal and Rohlf (1981). Results
T h e o r t h o g o n a l c o n t r a s t s i n d i c a t e d t h a t several distinctions c o u l d be m a d e b e t w e e n the c u l t i v a r s a n d the wild accessions. F o r e x a m p l e , c u l t i v a r s h a d a g r e a t e r p r o p o r tion o f their r o o t lengths infected (35 days), h i g h e r r o o t densities (35 days), h i g h e r s h o o t p h o s p h o r u s use efficiencies a n d s h o r t e r lifespans (Table 1). It a p p e a r e d , therefore, t h a t in s o m e w a y s the wild accessions, as a g r o u p , were b e t t e r a d a p t e d to soil infertility t h a n the cultivars (wild accessions h a d m o r e p r o t r a c t e d p h e n o l o g i e s ) while the cultivars were b e t t e r a d a p t e d in o t h e r w a y s (higher r o o t density). D e s p i t e this v a r i a b i l i t y , the cultivars exhibited g r e a t e r v e g e t a t i v e a n d r e p r o d u c t i v e r e s p o n s i v e n e s s to m y c o r r h i z a l infection (Table 1). To b e t t e r u n d e r s t a n d the p o s s i b l e c o n s e q u e n c e s o f t r a i t v a r i a b i l i t y in so far as m y c o r r h i z a l r e s p o n s e was c o n c e r n e d , a n a l y s e s emp l o y i n g m o r e degrees o f f r e e d o m were c a r r i e d out. W h e n i n o c u l a t e d , all accessions were all infected b y m y c o r r h i z a l fungi b y 35 d a y s (Table 2). N o fungi o t h e r t h a n m y c o r r h i z a l fungi were o b s e r v e d to be infecting the roots. T h e r e was a significant effect o f accession o n infected r o o t length ( % ) at b o t h harvests. H o w e v e r , b y the final harvest, the p e r c e n t a g e o f infected r o o t l e n g t h v a r i e d o n l y f r o m 41 to 5 9 % a m o n g accessions. T h e ten accessions differed in the w a y l e a f a r e a res p o n d e d to m y c o r r h i z a l i n f e c t i o n (Fig. 1). A c c e s s i o n s 6 a n d 10 s h o w e d no significant r e s p o n s e to m y c o r r h i z a l infection in l e a f area, while o t h e r accessions were p o s i tively responsive. Thus, a significant i n t e r a c t i o n b e t w e e n accession a n d i n o c u l a t i o n was a p p a r e n t (F(1,9)=9.33). A c c e s s i o n 6 is a wild accession, while A c c e s s i o n 10 is a cultivar. Thus, differential l e a f a r e a r e s p o n s e to infection was a p p a r e n t l y n o t r e l a t e d to a d i s t i n c t i o n b e t w e e n wild a n d c u l t i v a t e d accessions. Significant i n t e r a c t i o n s were also a p p a r e n t b e t w e e n accession a n d i n o c u l a t i o n in v e g e t a t i v e s h o o t weight, the n u m b e r o f fruits p e r p l a n t , t o t a l fruit weight a n d t o t a l seed w e i g h t (Table 3). In m o s t cases, the accessions were p o s i t i v e l y r e s p o n s i v e to infection. A c c e s s i o n s 1, 4, 5 a n d
85 Table 1. Results of orthogonal contrasts between all wild accessions and the two cultivars Variable Infected root length (%, 35 days) Infected root length (%, final harvest) Root density (NM plants, 35 days) Root density (NM plants, final harvest) Shoot phosphorus use efficiency (NM plants) Lifespan (NM plants) Vegetative duration (NM plants) Fruiting duration (NM plants) Total shoot response to infection (dry weight) Seed number response
df
Error mean square
Mean square
39
177
1652
38
65
F
Comment
9.4**
7.7
Cultivars higher
0.1 ns
40
0.069
7.01
37
0.632
7.99
12.7"*
Cultivars lower
36 36
0.0134 79.7
1.06 6160
79.3 ** 77.3**
Cultivars higher Cultivars lower
35
23.7
302
12.7"*
Cultivars lower
35
92.3
3832
41.5 **
Cultivars lower
79.7 ** 59.8"*
Cultivars higher Cultivars higher
38 38
0.0664 0.105
102"*
5.29 6.29
Cultivars higher
** Indicates significant at P < 0.01
Table 2. Mean (s.c.) percent of root length infected by mycorrhizal fungi a Inoculation treatment Infected rootlength 35 days (%) Infected rootlength final harvest (%)
Accession 1
2
3
4
5
6
7
8
9
10
Mb NM
53(3) 2(1)
39(4) 0(0)
58(11) 0 (0)
71(3) 0(0)
47(8) 0(0)
62(3) 0(0)
54(6) 0(0)
61(3) 0(0)
67(5) 0(0)
73(8) 0(0)
M NM
44(7) 1(1)
51(4) 1(1)
59 (4) 0 (0)
59(3) 0(0)
54(2) 1(1)
59(5) 0(0)
41(4) 0(0)
55(1) 0(0)
52(1) 0(0)
47(1) 0(0)
n=5 " Analysis of variance showed significant effects of accession (p < 0.005) on infected root length (%) at 35 days and at the final harvest bM = mycorrhizal NM = non-mycorrhizal 6, however, were poorly responsive in vegetative shoot weight. Accession 6 was poorly responsive in total fruit weight. Accessions 5 and 6 were poorly responsive in total seed weight. Significant interactions between accession and inoculation were also found in the weight of seeds per fruit (Table 3). Most wild accessions were unresponsive to inoculation in this variable, but the cultivars (Accessions 9 and 10) showed decreases in seed weight per fruit due to mycorrhizal infection. Inoculation did not significantly influence individual seed weight, but did have a significant effect on individual fruit weight for Accession 1. Thus, while the n u m b e r of fruits per plant was not affected by inoculation in Accession 1, total fruit weight was. In contrast, other accessions were responsive to inoculation in the n u m b e r of fruits per plant rather than the individual fruit weight. The cultivars (Accessions 9 and 10) tended to produce
fewer fruits and seeds per plant, but produced heavier seeds and fruits c o m p a r e d to the wild accessions (1-8). The proportional allocation of resources (biomass, nitrogen, phosphorus) within the shoot was, in each case, significantly affected by accession and in some cases, significantly affected by inoculation (Table 4). For example, Accession 10 had the lowest proportional allocation of biomass to seeds while Accession 3 had the highest. There was a significant positive effect of inoculation on allocation of biomass to fruits. There were also significant interactions between accession and inoculation for biomass allocation to the vegetative shoot, nitrogen allocation to the vegetative shoot and nitrogen allocation to the seeds. Nitrogen and phosphorus were preferentially allocated to reproductive tissues (to fruits and seeds for phosphorus and to seeds for nitrogen, see Table 4). Thus it followed that seed nitrogen and phos-
600 F 400
i
95gLSD
I 95% LSO
200
600
i
i
J
i
l
i
G 400
I
195% LSD/~/////D
95~ ks~
200
cu
600 H 400
f_ ro
I
~3
95g kSO
I ~5~ ,9~
/~ /
200
ro
/El
//
600
i
i
t
i
i
t I
400
~~
200
I 95~ LSO
4~//////
600 J
E
'
'
,
~ ljj
E
J
400 200
, ~ 10
~1~ 20
30
40
50
60 t0
20
30
40
50
60
Days from transplanting
Fig. 1A-,L Area of living leaves vs. time for mycorrhizal (i) and non-mycorrhizal (D) plants of Accessions 1 10, respectively
p h o r u s concentrations and fruit p h o s p h o r u s concentrations were significantly higher than for the vegetative p o r t i o n of the s h o o t (Tables 5 and 6). Again, significant interactions between accession and inoculation were a p p a r e n t for vegetative s h o o t nitrogen c o n c e n t r a t i o n and content, for fruit nitrogen concentration and for seed nitrogen content (Table 5). I n o c u l a t i o n usually resulted in a significant decrease in nitrogen concentrations o f the vegetative shoot, fruit and seed. F o r p h o s p h o r u s , significant interactions also existed between accession and inoculation, but in this case, the effect of inoculation was to increase p h o s p h o r u s concentration in the vegetative shoot, fruits and seeds (Table 6). Clear distinctions between wild and cultivated accessions were not a p p a r e n t for either resource allocation or nutrient concentration. It is a p p a r e n t f r o m the foregoing that mycorrhizal infection h a d differential effects on the various accessions. Some of the variation in total s h o o t response to infection could be attributed to variation in inherent capacity to a c c u m u l a t e p h o s p h o r u s (normalized for lifespan, see Fig. 2). Variation in inherent ability to accumulate p h o s p h o r u s a p p e a r e d to be due to variation in root density, as r o o t density was also correlated with total s h o o t response to m y c o r r h i z a l infection (Fig. 3). Thus, regardless o f whether they were wild or cultivated, the accessions with higher r o o t densities r e s p o n d e d to infection to a lesser extent t h a n those with lower r o o t densities.
Table 3. Mean (s.e.) growth and reproductive variables Accession 1 2 3 4 5 6 7 8 9 10
Inoculation treatment
Veg. shoot weight (g)
Seeds per plant
Indiv. seed weight (rag)
Total seed weight (g)
Fruits per plant
Indiv. fruit weight (g)
Total fruit weight (g)
Seed weight per fruit (g)
M NM M NM M NM M NM M NM M NM M NM M NM M NM M NM
12.5(0.6) 10.0(0.5) 14.6(0.6) 8.8(1.2) 11.8(0.5) 8.2(0.6) 13.7(0.6) 12.3(0.7) 17.0(0.8) 15.5(1.6) 14.1(1.3) 12.5(1.1) 14.5(1.4) 10.4(1.3) 15.5(1.8) 6.4(0.6) 8.1(0.1) 3.2(0.2) 15.4(0.5) 9.1(0.8)
1150 (27) 847 (71) 820 (80) 490 (72) 1550(120) 1250 (66) 1520 (87) 1100(104) 580 (22) 440 (63) 1180 (17) 1140(113) 580 (43) 290 (48) 1300(135) 680 (91) 500 (43) 180 (28) 420 (86) 260 (21)
1.7(0.1) 1.7(0.1) 1.7(0.1) 1.7(0.1) 1.0(0.0) 1.1(0.0) 1.2(0.0) 1.1(0.0) 2.1(0.1) 2.3(0.2) 1.2(0.0) 1.1(0.0) 2.3(0.1) 2.2(0.1) 1.4(0.0) 1.5(0.2) 2.5(0.0) 2.2(0.1) 2.6(0.2) 2.3(0.1)
1.9(0.1) 1.4(0.1) 1.4(0.1) 0.8(0.1) 1.6(0.1) 1.3(0.1) 1.8(0.1) 1.3(0.1) 1.2(0.0) 1.0(0.1) 1.4(0.0) 1.3(0.1) 1.3(0.1) 0.7(0.1) 1.8(0.2) 1.1(0.2) 1.2(0.1) 0.4(0.1) 1.0(0.2) 0.6(0.1)
10(1) 10(1) 9(1) 5(1) 30(2) 22(1) 27(1) 20(2) 10(I) 7(1) 25(1) 23(3) 10(1) 4(1) 21(2) 10(1) 6(1) 2(0) 6(1) 2(0)
0.77(0.02) 0.48(0.04) 0.38(0.03) 0.36(0.02) 0.10(0.00) 0.10(0.01) 0.12(0.00) 0.11(0.00) 0.52(0.03) 0.58(0.03) 0.11(0.00) 0.11(0.01) 0.43(0.02) 0.49(0.03) 0.26(0.01) 0.26(0.03) 1.15(0.29) 1.01(0.14) 0.69(0.11) 0.67(0.03)
8.0(0.5) 4.4(0.2) 3.3(0.2) 2.0(0.3) 2.9(0.1) 2.1(0.1) 3.1(0.2) 2.1(0.2) 5.3(0.4) 4.0(0.2) 2.8(0.1) 2.5(0.1) 4.0(0.2) 2.1(0.4) 5.6(0.7) 2.7(0.4) 5.8(0.9) 1.7(0.7) 3.8(0.5) 2.1(0.2)
0.19(0.01) 0.15(0.01) 0.16(0.01) 0.15(0.01) 0.05(0.00) 0.06(0.00) 0.07(0.00) 0.06(0.00) 0.12(0.01) 0.14(0.01) 0.05(0.00) 0.06(0.00) 0.14(0.01) 0.16(0.01) 0.09(0.00) 0.10(0.02) 0.22(0.03) 0.28(0.04) 0.13(0.02) 0.19(0.01)
< 0.0001 ns ns
< 0.0001 < 0.0001 < 0.05
< 0.0001 < 0.0001 < 0.01
< 0.0001 ns ns
< 0.0001 < 0.0001 < 0.0001
< 0.0001 < 0.01 < 0.05
Analysis of Variance Factor
Significance levels
Accession Inoculation Interaction
< 0.0001 < 0.0001 < 0.005
n = 5
< 0.0001 < 0.0001 ns
87 Table 4. Mean proportional allocation of resources within the shoot (%) Accession
Inoculation treatment
Biomass
Nitrogen
Veget. shoot
Fruits
Seeds
Phosphorus
Veget. shoot
Fruits
Seeds
Veget. shoot
Fruits
Seeds
I
M NM
55.9 61.0
35.5 29.5
8.6 9.5
36.4 37.8
27.3 27.4
36.3 34.8
15.4 24.4
44.4 27.5
40.2 48.1
2
M NM
75.7 75.7
17.2 17.1
7.1 7.2
46.1 54.4
17.1 16.7
36.9 28.9
39.4 39.9
28.3 18.6
32.3 41.4
3
M NM
72.4 70.6
17.7 17.9
9.9 11.5
45.7 41.9
16.6 17.1
37.7 41.0
39.6 33.9
24.8 16.6
35.6 49.5
4
M NM
73.6 78.6
16.9 13.4
9.5 8.0
50.7 64.2
11.0 9.2
38.3 26.6
41.8 37.5
22.9 16.5
35.3 46.0
5
M NM
72.1 75.3
22,6 19,9
5.3 4.8
68.3 67.0
14.2 15.9
17.5 17.2
29.2 36.1
43.2 29.6
27.6 34.3
6
M NM
77.2 76.5
15,3 15,6
7.5 7.9
71.2 70.2
3.7 4.4
25.1 25.4
39.0 39.9
24.0 17.7
37.0 42.5
7
M NM
72.5 79.9
20,8 15,1
6.7 5.0
68.4 74.5
6.6 7.7
25.0 17.8
38.9 49.2
30.5 20.3
30.6 30.5
8
M NM
67.7 63.7
24.2 26.1
8.1 10.2
65.4 50.7
7.5 18.4
27.1 31.0
32.3 30.9
30.3 25.5
37.4 43.7
9
M NM
54.0 63.3
37.8 29.1
8.2 7.6
46.1 58.1
22.3 22.9
31.6 18.9
21.1 25.8
41.5 32.6
37.4 41.6
10
M NM
76.3 76.8
18.7 18.1
5.0 5.1
63.1 62.5
14.1 18.4
22.7 19.1
40.2 43.1
31.5 23.0
28.3 33.9
