Flag Leaf Lamina Research Articles

Physiological and anatomical studies of two wheat cultivars irrigated with magnetic water under drought stress conditions

The aim of this study was to assess some physiological parameters and anatomical changes in two wheat plant cultivars (Triticum aestivum L. cvs. Sakha 93 and Sids 9) in response to irrigation with magnetized water under two levels of drought stress (field capacity (FC) of 75% and 50%) and the control (FC 100%) in two consecutive winter growing seasons (November 20 to May 5 2014/2015 and 2015/2016). Pot experiments were carried out in a greenhouse in the experimental farm of the Faculty of Agriculture, Menoufia University, Shibin El-Kom, Egypt. A water deficit, particularly at 50% FC, significantly decreased growth and parameter values, above all in Sakha 93, and disrupted most physiological aspects, biochemical constituents and internal structural features of both wheat cultivars. Irrigation with magnetized water alleviated the negative consequences of drought stress on most physiological and biochemical parameters to a variable extent: the whole plant dry weight, total water content, total soluble sugar concentration in leaves, total free amino acids and proline increased by about 32, 12, 17, 27 and 73%, respectively, under 50% FC drought stress in Sids 9 compared to the control. As the levels of drought increased, the grain yield (g/plant) decreased considerably, from about 81% in Sakha 93 at 50% FC to 26% in Sids 9 at 75% FC. The use of magnetic water increased grain yield from 61% in Sakha 93 at 75% FC to about 268% in Sids 9 at 50% FC. Magnetic water also increased the thickness of the flag leaf midvein and lamina, as well as the metaxylem vessel diameter of Sakha 93 by 28.8, 11.7 and 20.0%, respectively, compared to the control. The application of magnetic water increased the growth and the other parameter values studied in both cultivars but above all in Sakha 93, whereas Sids 9 produced more grain yield under all levels of drought stress. As the growth and grain production increased in both cultivars when using magnetic water, this study recommends this type of irrigation for these wheat plants, which are widespread in Egypt.

A quantitative genetic study for elucidating the contribution of glutamine synthetase, glutamate dehydrogenase and other nitrogen-related physiological traits to the agronomic performance of common wheat

To better understand the genetic variability for nitrogen use efficiency in winter wheat is a necessity in the frame of the present economic and ecological context. The objective of this work was to investigate the role of the enzymes glutamine synthetase (GS) and glutamate dehydrogenase (GDH), and other nitrogen (N)-related physiological traits in the control of agronomic performance in wheat. A quantitative genetics approach was developed using the Arche x Récital population of doubled haploid lines grown for 3 years in the field. GS and GDH activities, ammonium, amino acid and protein contents were measured at different stages of plant development in different organs after flowering. Significant genotypic effects were observed for all measured physiological and agronomical traits. Heading date was negatively correlated with ammonium, amino acid, protein contents and GS activity in the flag leaf lamina. Grain protein content was positively correlated with both ammonium and amino acid content, and to a lesser extent with soluble protein content and GS activity. A total of 148 quantitative trait loci (QTLs) were detected, 104 QTLs for physiological traits and 44 QTLs for agronomic traits. Twenty-six QTLs were detected for GDH activity spread over 13 chromosomes and 25 QTLs for GS activity spread over 12 chromosomes. We found only a co-localization between a QTL for GS activity and GSe, a structural gene encoding cytosolic GS on chromosome 4B. A coincidence between a QTL for GDH activity and a gene encoding GDH was also found on chromosome 2B. QTL regions combining both physiological and agronomical QTLs were mainly identified on linkage groups 2A, 2B, 2D, 5A, 5B and 5D. This approach allowed us to propose possible functions of physiological traits to explain the variation observed for agronomic traits including yield and its components.

Dynamics of light and nitrogen distribution during grain filling within wheat canopy.

In monocarpic species, during the reproductive stage the growing grains represent a strong sink for nitrogen (N) and trigger N remobilization from the vegetative organs, which decreases canopy photosynthesis and accelerates leaf senescence. The spatiotemporal distribution of N in a reproductive canopy has not been described in detail. Here, we investigated the role of the local light environment on the spatiotemporal distribution of leaf lamina N mass per unit leaf area (SLN) during grain filling of field-grown wheat (Triticum aestivum). In addition, in order to provide some insight into the coordination of N depletion between the different vegetative organs, N dynamics were studied for individual leaf laminae, leaf sheaths, internodes, and chaff of the top fertile culms. At the canopy scale, SLN distribution paralleled the light gradient below the flag leaf collar until almost the end of grain filling. On the contrary, the significant light gradient along the flag leaf lamina was not associated with a SLN gradient. Within the top fertile culms, the time course of total (alive + necrotic tissues) N concentration of the different laminae and sheaths displayed a similar pattern. Another common pattern was observed for internodes and chaff. During the period of no root N uptake, N depletion of individual laminae and sheaths followed a first-order kinetics independent of leaf age, genotype, or N nutrition. The results presented here show that during grain filling, N dynamics are integrated at the culm scale and strongly depend on the local light conditions determined by the canopy structure.

Photosynthesis of wheat in a warm, irrigated environment: II. Traits associated with genetic gains in yield

Net photosynthetic rate ( A n), stomatal conductance ( g s), intercellular CO 2 concentration ( C i), and chlorophyll concentration estimate ([Chl]) were measured on flag leaves of 30 random individual F 5 plants within each of eight F 2-derived bulks, from a cross between two spring wheat ( Triticum aestivum L.) cultivars, Seri-M82, and Siete Cerros-T66 contrasting in A n, and realized grain yield. Measurements were made on fully irradiated leaves of field plots growing in a warm, low relative humidity, irrigated environment. Average A n of F 2-derived families measured during grain filling ranged from 19.1 to 24.4 μmol m −2 s −1 among families, with standard errors ranging from 0.35 to 0.53. Based on measurements of A n of flag leaf lamina of individual plants, measured several times during grain filling, four plants from each of four bulks were selected for high and low A n to represent the range of genetic diversity within and among F 2:5 families. From each of these 16 selected F 5 plants, head rows were grown to generate inbred F 5:7 lines for replicated yield trials, which were sown in two environments in the same locality, differing by five weeks in sowing date, and having mean grain yields of approximately 3.5 t ha −1. Mean A n measured on randomly selected flag leaves of the inbred lines ranged from 16.3 to 24.6 μmol m −2 s −1 over both sowing dates. A n, g s, and C i all correlated with yield of inbred lines. Furthermore, A n and g s measured on individual F 5 plants correlated genetically and phenotypically with A n, g s, and yield of the inbred lines deriving from the same plants, in both environments where yield was evaluated.

Long-distance transport of cobalt and nickel in maturing wheat

Cobalt, nickel and strontium were introduced via flaps into leaf laminas or into the stem of maturing, intact winter wheat ( Triticum aestivum L., cv. `Arina') grown under natural conditions in a field. Long-distance transport of these elements and the influence of the application date and of different application positions were investigated. The dry-matter accumulation in the grains was not markedly affected by the treatments as compared to untreated control plants. The phloem-immobile strontium served as a marker for the distribution of the xylem sap in the plants. After foliar application, nickel accumulated more rapidly and in higher quantities in the grains than cobalt. Therefore, nickel has a slightly better phloem mobility than cobalt. Regardless of the application date, a higher percentage of the two elements was transported from the flag leaf lamina than from the second or third lamina from the top to the grains. These results indicate that the leaf position is highly relevant for the transfer of the heavy metals investigated to the ear. Introduction into the stem led to a higher accumulation of nickel and cobalt in the grains than introduction into one of the leaves. An earlier feeding date caused a higher accumulation of nickel and cobalt in the grains when introduced into the stem. In contrast, no major differences between earlier and later feeding dates were detected when the elements were introduced into the leaves. Losses of the applied elements were detected during maturation and can be explained by leakage in the rain.

Effects of weed competition on flag leaf photosynthesis and grain yield of spring wheat

Three pot experiments were performed at the University of Wales, Bangor, Gwynedd, UK during 1993 to determine if differences in the competitive ability of three annual weeds (Chenopodium album L., Sinapis arvensis L. and Phalaris minor Retz.) were related to their relative effects on leaf growth, gas exchange and nitrogen uptake of spring wheat (cv. Alexandria). In all experiments, wheat density (316 plants m−2) was similar to that in a commercial crop and five weed density treatments (between 0 and 600 plants m−2) were tested. Measurements of gas exchange were made on fully expanded, attached wheat flag leaves on four occasions between emergence and complete senescence in the control and highest weed density treatments. High weed density resulted in a lowering of net photosynthetic rate due to stomatal and non-stomatal factors. Lamina area and stomatal density of wheat flag leaves were decreased, and specific leaf area was increased by weed competition, but the effects on these variables were smaller than on net photosynthesis. Weed density did not affect wheat plant height, but dry weight, grain yield and total N-uptake were decreased with an increase in density of all weed species. The rank order of competitive ability of the species (C. album>P. minor>S. arvensis) was unaffected by weed density and was the same irrespective of whether it was based on the % decreases in wheat grain yield or in total plant dry weight. Averaged over the four measurements made during the grain-filling period there were only small differences between the weed species in their effects on net photosynthetic rate. However, when these were combined with effects on flag leaf area, there were larger differences in calculated net photosynthetic productivity, which were related to differences in the effects of weeds on grain yield. Differences in the competitive ability of weeds were not related to differences in their effects on wheat flag leaf lamina area, specific leaf area, stomatal density or total nitrogen uptake. Differences in competitive ability between weed species were not related to differences in weed plant height, dry weight or nitrogen uptake. It was concluded that the observed effects of weeds on wheat were due either to shading, or to competition for a nutrient other than nitrogen.

Role of Flag Leaf and Spike Emergence Stage on the Incidence of Karnal Bunt in Wheat.

Removal of the flag leaf of wheat, earlier hypothesized to act as a site where secondary sporidia of Tilletia indica multiply and conjugate, reduced the severity of Karnal bunt. Evidence reported here suggests that sporidia reach the flag leaf from the soil by splashing, multiply on the surface of the flag leaf, and move with rain water or dew into the boot of the flag leaf to cause infection of the spikelets. Plants in growth stage 49 (first awns visible) were more vulnerable to infection by secondary sporidia than were plants at other growth stages. At growth stage 49, the flag leaf lamina was fully opened, compared with its preceding stages, which had tubular and closed lamina. Also, leaf posture of the flag leaf at growth stage 49 is erect and thus may facilitate movement of sporidial inoculum into the boot. Upon completion of stage 49, the flag leaf becomes droopy, leading to lesser inoculum movement into the emerging spike. Thus, maximum success can be achieved in artificial creation of Karnal bunt by inoculating with secondary sporidia before onset of growth stage 49. Genotypes whose maturity avoids coincidence of this critical stage of spike emergence with periods of weather favorable for infection by T. indica may be selected for resistance breeding.

Transport of Cadmium via Xylem and Phloem in Maturing Wheat Shoots: Comparison with the Translocation of Zinc, Strontium and Rubidium

Abstract The toxic heavy metal cadmium is taken up by plants and may contaminate harvested parts of agricultural crops. In the experiments reported here, cadmium was introduced together with markers for phloem (rubidium) and xylem (strontium) transport, either into intact shoots via a flap below the flag leaf node, or into detached shoots via the cut stem. Cadmium introduced into intact plants was redistributed during maturation from the peduncle and the flag leaf lamina to the grain. In detached shoots, some cadmium was removed from the transpiration stream, as judged from the comparison of shoots steam-girdled below the ear and of controls with an intact phloem in the peduncle. A minor quantity of cadmium was transported to the grain via the phloem in control shoots while a high percentage of this element was retained in the peduncle. The cadmium content of the grain increased in response to the increased cadmium concentrations in the feeding solutions (0.1 to 10 μ m ). The cadmium content of the grain was slightly lower when zinc (>10 μ m ) was introduced at the same time as cadmium (1 μ m ).

Planting density effects on assimilation and partitioning of photosynthates during grain filling in the late-sown wheat

Leaf blades of the late-sown winter wheat produced the major portion, i.e., more than 60 %, of the total 14C-photosynthates at grain filling, but ear (rachis and glumes) only about 15 %, sheaths about 11 %, and stem internodes about 11 %. The change of plant density in this experiment had little influence on the 14CO2-photoassimilation of the ear (rachis and glumes), flag leaf lamina, sheaths and stem internodes, but markedly affected photosynthesis of the second, the third and lower leaves. The photosynthetic rate [expressed as specific radioactivity, s-1 kg-1(d.m.)] and the amount of 14CO2 photosynthates decreased significantly in the second, the third and other lower leaves at a high plant density. Upon grain-filling of the late-sown wheat, the grain was the major importer of photosynthates. Yet partitioning to the stem internodes depended on the plant density. Stem was the importer of photosynthates at a low plant density, but the exporter at a high plant density. In plants at a low plant density a fairly large proportion of photosynthates was distributed into the roots. The middle and lower above-ground parts of the late-sown wheat at a high plant density decreased or lost their function early. As a result, the plant senesced earlier. However, the grain setting, filling and yielding were restricted. An appropriately low plant density was suitable for prolonging the function of the middle and lower organs, delaying the senescence of plant, increasing the source supply for grain filling, and improving the grain yield.

Effect of locally increased zinc contents on zinc transport from the flag leaf lamina to the maturing grains of wheat

Abstract From previous experiments, it was evident that the accumulation of zinc in maturing wheat grains is highly regulated, but the regulatory mechanisms involved are not yet identified. In this study, we determined the transfer of radiolabelled zinc (fed directly into a leaf flap) from the flag leaf lamina to the grains. We also determined how this zinc transfer was affected by feeding additional unlabeled zinc (1 μmol per plant) either into the flag leaf sheath or the peduncle. Most of the 65Zn was retained in the feeding flap. A high percentage of the zinc exported from the flap accumulated in the grains with little accumulation of radiolabel in the other parts of the shoot. Unlabeled zinc remained mainly in the feeding flap and in the parts reached by the transpiration stream from the feeding position. The transfer of radiolabelled zinc was essentially not influenced by unlabeled zinc fed into another plant part. Our results suggest that the loading of zinc into the phloem and the mass flow in the ...

Effect of Phloem Interruption on Endopeptidase and Aminopeptidase Activities in Flag Leaves of Field-grown Wheat

Leaf senescence and nitrogen remobilization in field grown wheat can be affected by steamgirdling (phloem interruption). The peduncle (below the ear) or the base of the flag leaf was steamgirdled 1 or 10d after anthesis. Protein contents, free amino acids and peptide hydrolase activities were analyzed throughout the maturing period in extracts of the flag leaf lamina from treated plants and untreated controls. Phloem interruption at the leaf base initiated a rapid net degradation of proteins and an accumulation of free amino acids (mainly glutamine and proline). Azocaseinase activity at p H 5.0 increased during the first week after this treatment and declined afterwards, while the activity at p H 9.0 peaked late during senescence when most of the leaf proteins were already hydrolyzed. Aminopeptidase activities (measured with 8 different substrates) remained at the original level for about one week before they decreased. From this time course it appears possible that aminopeptidases contributed to the complete degradation of leaf proteins. Steam-girdling below the ear slightly delayed the remobilization of proteins in the flag leaf lamina, the increase in endopeptidase and the decrease in aminopeptidase activities. The contents of free amino acids remained higher than in untreated controls. The catabolism of leaf proteins and the pattern of peptide hydrolases were differently influenced by the two treatments.

Transport of Rb and Sr to the ear in mature, excised shoots of wheat: Effects of temperature and stem length on Rb removal from the xylem

Wheat (Triticum aestivum L. cv. ‘Arina’) shoots grown in the field were excised post-anthesis and incubated in the laboratory for 72 h standing in 2 mM RbCl+2 mM SrCl2. Strontium is a phloemimmobile, xylem-mobile element and indicates the distribution of the xylem sap in the plant. Rubidium is easily transported in the phloem and behaves similarly to the highly mobile K as far as the redistribution within the plant is concerned, although Rb cannot substitute physiologically or biochemically for K. The Sr contents in the ear were hardly affected by stem length or by steam-girdling (phloem-interruption). Rubidium on the other hand accumulated in the stem. A peduncle length of 5 cm was sufficient to decrease the Rb concentration in the xylem by more than 50% at 25°C. Only a minor quantity of Rb reached the ear after passing through 20 cm of stem without nodes and this transport was prevented by steam-girdling. A remarkable flux of Rb into the ear was observed in shoots with a vascular connection between the flag leaf lamina and the ear. Our results suggest that Sr was transported with the transpiration stream, while Rb was rapidly eliminated from the xylem and reached the ear via the phloem. The temperature optimum for the removal of Rb from the xylem was around 35°C. The nodes may further contribute, but are not prerequisites for this redistribution. The observed transfer processes could allow a solute specific transport via the xylem and phloem of maturing cereals and may be an important factor influencing the nutrient economy in the field.

Effect of Phloem Interruption on Senescence and Protein Remobilization in the Flag Leaf of Field-grown Wheat

Summary The phloem represents a link between senescing leaves (sources) and maturing (major sinks) in plants characterised by monocarpic senescence such as cereals. The redistribution of nutrients and assimilates might be involved in the control of senescence on a whole plant level. Field-grown winter wheat was steam-girdled at the base of the flag leaf lamina or below the ear in order to interrupt the phloem at these positions and to identify effects on flag leaf senescence. A phloem interruption below the ear delayed senescence of the flag leaf lamina as judged by chlorophyll contents and activities of assimilatory enzymes (phosphoribulokinase, glutamine synthetase). The rate of net photosynthesis was lowered in these leaves during the first week after the treatment, recovered and remained afterwards higher than in those of untreated control plants. Steam-girdling at the base of the leaf initiated its rapid senescence. The rate of photosynthesis declined rapidly after this treatment and was completely lost within one week, while dark respiration was initially slightly stimulated and decreased later than photosynthesis. The good correlations between enzyme activity measurements and immunoblot analyses indicate that not only the activities, but also the quantities of assimilatory enzymes were reduced. The interruption of source/sink relations affected flag leaf senescence, but the effects strongly depended on the position of the treatment. Leaf constituents were rapidly degraded after steam-girdling at the leaf base, although the export of breakdown products became impossible.

Variation in Chlorophyll Content of Rice Flag Leaf Lamina and Sheath

Variation in Chlorophyll Content of Rice Flag Leaf Lamina and Sheath

Transfer of Rubidium from the Xylem to the Phloem in Wheat Internodes

Summary Wheat ( Triticum aestivum L., var. «Arina») was cut below or above the flag leaf node. The detached shoots were incubated standing in a solution containing 2 mM RbCl and 2 mM SrCl 2 . Source/sink relations were modified by steam-girdling the stem below the ear (phloem interruption) or by removing the ear or the flag leaf lamina. Strontium (mobile in the xylem, but immobile in the phloem) was distributed in the detached shoots as expected from transpiration data. Rubidium on the other hand accumulated in the stem and in the leaf sheath of illuminated plants, but only minor quantities were detected in the leaf lamina and in the ear. The node was not a prerequisite for the removal of rubidium from the transpiration stream. The rubidium content of the ear was further decreased by removing the leaf lamina, and the flux of Rb (but not of Sr) was essentially blocked by steam-girdling below the ear. The results from these experiments suggest that Rb was transferred efficiently from the xylem to the phloem in wheat internodes. The mechanisms involved, the regulatory interactions, the selectivity and the physiological significance must be investigated in future experiments. Such transfer processes might be important for the channelling of solutes in maturing wheat.

Morphological studies on the regularity of shoots development in rice plants. I. Different growth types indicated by total leaf number on the main stems in the same plot.

Even when rice seedlings with uniform size and age were planted as the singling in each pot containing the same amounts of nutrients and were precisely cultured at outdoor, a difference of one leaf frequently appeared in the total leaf number of the main shoots, one had N leaves and the other N-1 leaves. It is already known that the difference is a kind of individual variation. However, morphological aspects of the difference are not yet clearly demonstrated. Morphology of the main shoots were compared between the plant group having N leaves and that with N-1 leaves in total leaf number on the main stems. Morphological characters analyzed were the changes in the length of leaf laminae, leaf sheaths and elongated internodes successively developed on the main stems. Morphological variations based on the changes were clearly revealed inter groups but not intra groups (Figs, 1 and 2). The variations inter groups as follows. 1) Although the change in successive lamina length resembled in both groups up to the N-1 leaf position on the stem, the flag leaf lamina of N leaf group is conspicuously shorter than that of N-1 leaf group. 2) Although the change in successive sheath length resembled in both groups up to the N-2 leaf position on the stem, a quite different pattern was shown at the leaf positions more than N-2 leaf 3 on the stem. 3) The successive internode length on the main stem with N-1 leaves, which had five elongated internodes, linearly increased. The main stem with N leaves had six elongated inter-nodes. Culm length of the main stem was relatively greater in N-1 leaf group than N-1 leaf group. However, the length of each two successive internodes in upper positions was relatively greater in N-1 leaf group than N leaf group. Two different morphological types, which are indicated by the above-mentioned characters can be regared as a kind of "growth type". These two growth types are responsible for the variation shown at the total leaf number on the main stem under this experiment precisely cultured, and they occur within single cultivars assumed to be a "pure line". Even these types appeared in the precisely culture condition, therefore they seems to be present in the culture condition of conventional breeding experiment.

Glaucousness in Wheat: Its Development and Effect on Water-use Efficiency, Gas Exchange and Photosynthetic Tissue Temperatures*

Glaucousness, which is the visual manifestation of epicuticular wax, has previously been found to increase the yield of grain and dry matter of droughted wheat. This study was designed, first, to monitor the development of epicuticular wax in a pair of durum (Triticum turgidum L. var. durum) wheats isogenic for glaucousness and, second, to determine the likely reasons for increased yields of glaucous durum and common (T. aestivum L.) wheats over their non-glaucous isogenic counterparts. Glaucousness first appears on the leaf sheath at the time of stem elongation. It rapidly reaches maximum expression, particularly on the flag leaf sheath and the abaxial surface of the flag leaf lamina, as well as on the emerging head. In glasshouse experiments using isogenic pairs of both common and durum wheats, the water-use efficiency measured between sowing and maturity in droughted treatments was on average 9% higher in the glaucous lines. Glaucous leaves were retained longer than non-glaucous leaves in the droughted treatment but not in the irrigated control. In droughted field-grown plants, temperatures of photosynthetic tissues were up to 0.7"C cooler in glaucous than non-glaucous lines, depending on the time of day. Similarly, in well-watered glasshouse plants, glaucous plant parts were on average 0.3"C cooler than non-glaucous plants. Gas-exchange studies of the durum lines in both irrigated and droughted treatments in a glasshouse indicated that ears of non-glaucous plants had higher rates of photosynthesis and day- and night-time transpiration, a higher stomata1 conductance and a greater rate of increase in photosynthesis with increasing light levels. However, the ratio of photosynthesis to transpiration was higher in the ears of glaucous plants. No differences were found for flag leaves when the adaxial surface was exposed to light. This study further documents that glaucousness can be a yield positive character under water-limited conditions, primarily through its effect on wateruse efficiency, on an extended period of transpiration and on the timing of the deposition of wax.

Relationships between grain yield and morphological characters in the winter wheat genotypes of the Belgian national list

Yield per shoot and to a much lesser extend yield per unit area were related to morphological characters. The flag sheath was better related to shoot yield than were any of the three uppermost leaf laminae. Among these the areas of the two lower leaves showed a better relationship to the yield than did the flag leaf lamina. Variation in main shoot yield was associated mainly with variation in grain number. More attention should be given to morphological character related to spike development before anthesis.

Effects of flag leaf axial lesions caused by Septoria nodorum on 14C translocation and yield of wheat

Wheat flag leaves having axial lesions caused by infection with Septoria nodorum were studied to determine how grain yield was affected and whether there was interference with translocation of carbohydrate. Kernel yield was reduced less than 5% when the axil and sheath of the flag leaf were the only tissues infected. When all leaves except the flag leaf were removed, kernel yield was reduced 14%, and when all leaves were removed, the reduction was 19%. After administration of glucose-U- 14C, translocation of 14C from the flag-leaf lamina to the developing kernels was not impeded; rather, in some instances, it was enhanced by infection with Septoria. In addition, glucose- 14C was metabolized more readily to ether-soluble components in infected tissue than in control tissue. Because axial lesions did not interfere with translocation of assimilates, the yield damage must have been caused by interference with other metabolic functions.

Mutation in Internode Length Affects Wheat Plant-Type

A mutant form was found in an M(2) population of wheat Triticum aestivum L. em. Thell. (aestivum group) 'Seneca'. The population was derived from soaked grains treated with 3.2 kilorads of gamma rays. The first and second internodes below the spike were reduced in length 33 and 15 percent, respectively, and the total height was 18 percent shorter than the prototype. The flag leaf sheath was normal in length resulting in spike placement below the flag leaf lamina. Segregation data suggest that one dominant gene controls this character. The canopy structure of a population of mutant plants is different from that of the normal type; therefore, this mutant can be used to evaluate light interception and physiological aspects of crop productivity.