This article tries to make a comparison of the rich knowledge of plant physiology in "Chi Min Yao Shu" with the historical data on the development of the early western plant physiology in the following nine fields such as water relation, mineral nutrition, transloeation, seed treatment, rapid assay of seed viability, vernalization, growth and development, sexuality and storage of crop products. This article restores historical truch and sings the praise of the working people in ancient China for their great contributions in plant physiology.

Sediments of palaeogene period accimilated in the Qingjiang Basin of Kiangsi province are divided into two successional formations, the upper Lingjiang and the lower Qingjiang formations. Both are mainly of lacustrine in origin. In these sedi- ments numerous spores and pollen are well preserved. The palaeogenee flora of that region is very rich, in which 147 palynomorphs of 66 families have been identified. One new genus Rutaceoipollenites and 9 new species namely Rutaceoipollenites archiacus, Sapotaceoidaepollenites tricolporatus, Lonicerapollis scabratus, Quercoidites minor, Tricolporopollenites aspidoporatus, Tricolporopollenites minutus, Boehlensipollis qing- jiangensis Poentapollenites, and Jiangsiensis are described. The palynological features of these formations are stated as follows: 1. The lower part of Qingjiang formation is characterized by the predominance of Ephedra. Because of the occurrence of Schizaoisporites, Aquilapollenites Extratri-poropollenites and pentapollenites, the age of this part is, therefore assigned to late paleocene-early Eocene, and the flora at that time seems to be of desert in nature. The climate was warm and dry. 2. The upper part of the Qingjiang formation is predominated by Tricolporopollenites minutus, Quercoidites minor and pollen' of sapindaceae and Ulmaceac, which indicates that the flora was subtropical and tropical in nature. The climate then changed to humid and hot. The age of this part is assigned to middle-late. Eocene. 3. The Lingjiang formation is predominated by the pollon of Taxodiaceae and some abundant subtropical and tropical elements. These features indicate that at that time some coniferous and broad-leaved mixed forests would have been flourishing on the hills of that region. The climate was then humid and warm. The age of the Lingjiang formation is assigned to early Oligocene.

Guizotia abyssinica (L.) Cass., the famous oil seed plant origin endemic to Ethiopia has been newly introduced from abroad and successfully propagated in different localities of Yunnan province. Botanical, phytochemical, pharmacological and cultural studies have been investigated on this plant. The experimental results show that Guizotia is a plant with wide adaptability. It is suitable for planting on the red soil hillocks throughout the Yunnan plateau, and technique of cultivation is simple. The oil content of seeds is rather high, and its fatty acid component is essentially linoleic acid. It may be used as edible oil. The pharmacological experiments on animals indicated that the oil can also be used as a certain remedy for artereosclerosis. So, Guizotia abyssinica is an oil plant with a greay economical future. We plan to cultivate it extensively in our province, as well as other southern provinces.

We studied the growth, morphology and yield of wheat in relation to manuring and watering. The results obtained were as follows: 1. The bigonovs stage is the critical period for increasing spikelet number and effective tillers. 2. The floret differentiation stage is an important period for retaining flowers and increasing grain number. When bloret reached the stage of stigma differentiation, almost all of them could develop into fertile flowers, so that stigma differentiation was enhanced and its growth period was prolonged. Therefore the number of sterile florets was decreases. 3. It has been found that there is a cerrelation among the leaves, stems and spikes in gowth, According to the gross morphology, the stimulative effects of manuring and watering on the particular organs may be predicted. 4. At the shooting up stage in early spring, application of manure and water will promote the elongation of second and fourth leaves, first and second basal internodes. This is the most suitable time for raising effective tillers. But inappropriate application of them may cause lodging. 5. At the shooting stage, manuring and watering will promote the elongation of fourth internode and that below the spike. This measure can prevent florets from degeneration.

The distribution of 14C-assimilates and the activity of starch synthetase during the grain filling period in wheat treated with 0.25% CCC were determined. The results showed that treatment with CCC at tillering stage influenced the distribution pattern of 14C-assimilates and the activity of starch synthetase differently at different stages of the grain filling period. Application of CCC retarded the movement of 14C into the grain and reduced the incorporation of 14C into the acid hydrolyzable fraction of the grain at the early stage but accelerated both of them at the later stage of grain filling period. Assays of starch synthetase activity indicated that CCC inhibited the activity of the enzyme at the early stage but promoted its activity at the later stage of the grain filling period. The significance of these findings is discussed in relation to the increase in sink capacity of the grain and to the increase in grain weight.

Due to delayed sowing and transplanting and late earing, of the late season rice, it is easily damaged meets by low autumn temperature, resulting in empty seeds and decreased yield too early sowing and earing result in small ears and decreased yield due to insufficient vegetation period. Climatic conditions differ from year to year, it is difficult to determine the proper sowing and transplanting time of any one year. By the uae of statistical, analysis we arrived at a temperature-light formula for calculating the duration of growth period in different varieties of late season rice. Using this formula, one may analyze climatic data for a period of many years, to obtain safe sowing and transplanting time in different rarities of late season rice for any particular year.

The growth and development of the parents in hybrid rice under the autumn conditions have been investigated. The observations include the growth and development phases, the growth of leaf blade, the florescence and time of flowering. The problems concerning the safe pollination time for successful fruiting and simultaneous blooming period for both maternal and paternal parents have been rather well solved, and we used the techniques such as the increase of pollen production in paternal parent line and of the effective spikes, the grain number per spike and the rate fructification in maternal parent line etc. to raise the yield of the seed field of ten thousand mu.

Cultivation of sugar beet in the central and southern parts of our country is a new thing during the Proletarian Cultural Revolution and is one of the most promising ways for developing our sugar production. In Yountze River area, it is practicable to grow sugar beet in the autumn, over- winter in the field and harvest in the next spring for the purpose of avoiding seasonal competition with cereal crops. In general, however, overwintered beet plants always bolt and have to be harvested before the beginning of April, because bolting cuts down sugar content significantly and also make processing difficult due to lignification of the roots. Inhibition of bolting may result in extension of growth period of the crop so that higher yield of root and sugar can be obtained. According to the results of experiments carried out in the last three years in Shanghai, Kiangsu, Chekiang and Hunan, it has been proved that bolting of overwintered autumn sown sugar beet can be effectively retarded by foliar application of maleic hydrazide at the concentration of about 0.3%, 7–10 days before bolting. With this method, the harvest time can be delayed about one month. Examination of the actual benefit of this method was made for the first time in the field of Miloo River Farm of Hunan province in this spring. Harvest time was delayed 24 days with MH treatment. The yield of beet roots per mu and total content of sugar per mu calculated according to the sugar content of the beet roots at the harvest time, are both increased remarkably as compared with that of the control. Residue of MH in the beet roots, determined one month after treatment with 0.4% MH solution, is onty 1.7 ppm. It is reasonable to suppose that the residue of MH in sugar should be negligible.

Using medium maturing varieties of early rice from Kwangtung province as ma- terials (Pearl dwarf etc.) and by method of varietal comparison, we have made inves- tigations on some physiological and ecological factors which affect rice yield. On the basis of experimental results obtained in our laboratory some approaches of increasing the efficiency for solar energy utilization and the apllication of these results to rice breeding, reform of cultivation system and high yielding culture measures have been discussed. Our experimental results obtained in 1974 and 1975 showed that a significant positive correlation is present between rice yield and the sum of leaf arza indices (LAI) at young panicle differentiation, full (80%) heading stage and 20 days after full heading stage. In case of LAI values less than 6, there is also a significant positive correlation between canopy net photosynthesis rate and LAI. In case where LAI values are higher, those varieties with little leaf openness all give move grain yield than variety with greater leaf openness (except for one variety lodging). In 1974 the total solar energy during the 90 days after transplanting was more than that in 1975, and the average grain yield in 1974 was also higher than that in 1975. The relationship between rice yield and LAI, leaf openness, solar energy can be expressed by a linear regression equation with three arguments. Using the method of so-called "cyclic prediction" (an unpublished new method) to examine the exactness of such a regression, the average error between calculated and actual values of rice yield is 2%, the maximum error is 5%. This indicates that the above three are indeed important factors affecting rice yield.

Treated with Ethrel at the concentration of over 3000 ppm at four different stages of the pollen development in wheat, our experimental results showed that Ethrel was very effective in inducing male sterility for the three earlier stages in Pal-you-boa, whereas it was ineffective for Tai-shan No. 1. Four types of anther and pollen development were found ofter the treatment with Ethrel: anther without pollen, anther with abortive pollen, anther with mixed pollen and anther with 3-nucleate pollen. In former three cases, the degree of sterility was rather high while in the last the degree of sterility was low and it was useless in production. The last type of development appeared in Tai-shan No. 1 and Pal-you-boa treated with Ethrel at the stage of 2-nucleate pollen. No abnormality was observed in the development of the tapetum in anther without pollen and anther with mixed pollen. In anther without pollen the tapetum and pollen became abortive simultaneously. It seems that there is no causal relation between them.

In the course of maturation of cotton bolls spraying with ethrel (200–2000 ppm) on cotton plant has a marked hastening effect on ripening. The bolls of treated plants cease to grow, rapidly mature and dehisce to emit fibers. For the fully grown bolls (middle and lower fruiting branches of cotton plants) both the boll weight and fiber quality are slightly improved, while for the rapidly growing bolls (upper fruiting branches.), the boll weight decreases. At the same time the leaves, flower buds and young bolls (less than 10 days old) shed. The higher the spraying concentration the more rapid and stronger the accelerating effect. At the time of spraying, the presence of too many young bolls and the use of an excess concentration, will effect both the yield and quality of cotton. Based upon the experimental results, a rational application of ethrel for the purpose of hastening the ripening of the cotton bolls has been proposed.

Field experiments in 1970–1975 showed that application of 0.75–1.00% of sodium ethylxanthate at the late milk-ripe stage by a foliar spray increased the water loss from the grain and hastened the yellow-ripe processes without any significant effect on the grain-filling processes of the cereals. The treatment caused an earliness in spring wheat, winter wheat, barley and rye for 5–7 days. The 1000-grain weight was decreased by 5% or was increased slightly depending on the locality and the cultivar used. There was no adverse effect on grain characters and its germination capacity by the treatment of sodium ethylxanthate. The crude protein content of the grain was slightly increased whereas the starch content was decreased by the treatment. It was considered that the accelerated less of water from the grain and rapid accumulation of dry matter in the grain may be responsible for the earlier maturity of cereals by the trestment of sodium ethyLxanthate. Effects of sodium ethylxanthate treastment on the translocation and accumulation of materials in cereal grain during maturation were studied with 144CO2 as a tracer. The results showed that under the influence of sodium ethylxanthate, the mobile sugars were increased in stems and leaves, and the translocation of assimilates to the grains as well as the accumulation of dry matter in the grain were not affected.

In 1964, we some young teachers and students in C-Y Agricultural School began to study "Three Lines" in rice (the male sterile line, the maintainer line and the pollen fertility recoverer line). In 1964—1965, we found six natural male sterile plants, but had not found an good maintainer line until 1970. Since then, under the steady leadership of our party and sincere concern by Chairman Hua Kuo-feng, the whole country has launched a vigorous mass movement of breeding "Three Lines" in rice and developed socialist cooperation. We have brought the spirit of self reliance and hard struggle into full play. On the basis of discovery of wild male sterile line in rice, we did numerous cross experiments with the rich resources of rice varieties in our country. In 1972, the maintainer line and the male sterile line were discovered and in 1973, the pollen fertility recoverer line was found. Thus we succeeded in the "Three Lines". During 1974—1976, by experimental plot, demonstrative planting and populization over wide areas, good result was finally obtained and the output of rice increased by 20%–30%. This is not only a new way to increase the output by a big margin, but also enrich the theory and practice in plant genetics and breedding.

We have studied biochemically the "Three Lines" (the male sterile line, the maintainer line and the pollen fertility recoverer line) and found that proline in the sterile anther is lower than that in control. Thus the retardation of sugar metabolism and the decrease of amino acid may be one of the important factors responsible for male sterility of rice.