ANALYSIS OF GROWTH

The pattern of growth throughout the life cycle of plants is characterized by a growth function that is called the Sigmoid curve-shaped growth curve of S. Quantitative study of the growth that has been accepted in general is dry weight, both of whole plants, or parts thereof. Dynamics and growth analysis mainly aims to measure the ability of plants as producers fotosintat (assimilat) expressed by dry weight. It is based on the fact that 90% of the dry plants derived from the photosynthesis. Basic concepts and physiological implications of the growth analysis is relatively simple and has been used extensively. 

Leaf is the main organ of photosynthesis which in turn will develop biomass (dry weight) of plants. Thus, the growth in the analysis only two variables was observed that dry weight and leaf area measured at certain intervals. Observation time interval is usually 2-3 days for fewer number of plants or 1-2 weeks for more number of plants. 

Measurement of leaf area can be done in various ways including:• the use of linear analysis of leaf area regeresi = a + b (pxl), use formula leaves; leaf area = leaf length (p) x width of the leaf (l) x constant (c).• The use of leaf projection method with the formula: leaf area = A / B x Z, where a = b = slope, p = leaf length, leaf width l =, c = constant, A = weight of leaf projection, B = weight of standard paper , and Z = area of ​​standard paper.• The use of millimeter paper, leaves in the picture on graph paper so that the leaf area can be calculated by summing all the boxes of milliliters in the projected image of leaves.• Area meter: all dirompes leaves, placed on the conveyor belt of the area meter - wide can be read• Use of electrical equipment such as leaf area meter, photoelectric, Canopy analyzer and so on, can be read directly on the leaf area. 

Plant physiologists in general to analyze the growth of a plant community because it shows the overall results of the plant, both the economic and biological results. Aanalisis plant growth usually aims to determine and explain the variation seen in the crop caused by genetic variables and environmental variables that affect plant growth. Data of observations of variable-variable observations can be used as a reference in designing the system settings that will improve crop plants photosynthesize.

Growth analysis components that many do is: (1) plant leaf area index (LAI), leaf area ratio (NLD), relative leaf growth rate (LPDR), leaf mass area (MSD), specific leaf weight (BDS) , Lajua net assimilation (LAN), rate of planting tumbub (LTP), and rate the relative tumbub (LTR).

Crop Growth Rate (LTP = LGR) and Relative Growth Rate
The growth rate of plant dry weight is expressed in the whole plant (g / plant / day). The more common measurement is the rate of crop growth is the growth rate of crop dry weight per unit area of ​​land within one unit of time is expressed in g. m-2.hari-1. In the mathematical calculation is expressed as dw / dt. Classical approach is to calculate the growth rate of an average crop for the time period between two successive sampling times. 

A concept analysis of pertumbuha for the initial phase of growth is the relative growth rate (LTR) is the dry weight increase per unit dry weight that has been assimilated into the plant, mathematically: LTR = 1 / w. dw / dt 

Leaf Area Index and Leaf Rate Unit 

Watson (1947) apply a concept of leaf area as a measure of the ability to crop cultivation in the determination of Leaf Area Index (LAI). ILD is the green leaf area (not age) per unit area of ​​land.At the individual plant, leaf area index is the ration between the leaves with a broad leaf stands or projection. Unit leaf rate is defined as an increase in plant dry weight per unit time per unit area of ​​leaf. Unit leaf rate are often called net assimilation rate (LAN) or Net assimilation rate (LAB). LAN can be viewed as a measure of the efficiency of each unit area of ​​leaf photosynthesis to increase the plant dry weight. LAN can be expressed mathematically by the formula = 1/ld LAN. dw / dt. LAN on average during the sampling period. 

If the LAN is the average size of net CO2 exchange rate union in the plant canopy leaf area, then multiplying the LAN with ILD be obtained LTP. So that LTP = LAN x ILD.LAN highest value when the plants are still small and most of the leaves are exposed to direct sunlight. LAN is likely to decline at the time of leaf area increment, and is unable to perform photosynthesis is optimal. Thus there will be a time when LTP no longer responsive to an increase in ILD. LAI reached a maximum at the time of LTP called Optimum ILD. Further increase in leaf area resulted in an increase in ILD, the leaves will overlap with each other than from the LAN to decline. LAN such impairment will result in decreased growth rate. ILD during LTP or LTR called ILD Criticism began to decline. 

Leaf area ratio (NLD) 

Net assimilation rate as a parameter analysis of the growth can be attributed to the relative growth rate over the leaf area ratio (NLD). NLD is a specific leaf area to form the whole plant and leaf area and is calculated based on total plant dry weight. The relationship between the LTP with the LTR LAN through the NLD mathematically is:LTR = LAN x NLD 

Analysis of Growth, CO2 Fixation and Growth of Plant Cultivation
Plant biomass is the result of accumulation of carbon dioxide in the process of photosynthesis asimilat during growth. The process of photosynthesis is the absorption of solar radiation energy through the reduction of CO2 with H2O on a subsequently backfilled by plant tissues produce biomass storage. Thus, the factors that affect plant biomass is the amount and efficiency of absorption of solar radiation in the process of CO2 fixation. 

Leaves are the main organs of plants to perform photosynthesis process in CO2 fixation. With the development and condition of the maximum possible rate of growth of leaves of plants.In the analysis of plant growth, the main parameters used in assessing the growth rate of plants is the leaf area, leaf developmental state of plant biomass. Therefore the further discussion will try to see the relationship between the analysis of growth and CO2 fixation in photosynthesis. 

Leaves broad and Plant Growth 

Leaves as the main organ of photosynthesis should be able to efficiently absorb light radiation to support growth towards better productivity. Plant leaves usually emerge from the embryo or meristem tissue of the stem or branch, especially in annual crops (perennial). On annual crops (annual), especially those bred in the generative, the first leaves develop from the embryo (seed) da is small throughout the growth cycle, allowing greater absorption of solar radiation sebahagian generate heat energy (sensible energy). 

In the class of C4 plants (class of efficient plants) tend to generate growth in the early development of the leaf is more dominant. This allows more efficient utilization of solar radiation. In agronomic practices such conditions can be manipulated through the narrow spacing settings to improve the soil so that the closure of anggot absorption of solar radiation is higher. 

Agriculture is basically associated with increased plant efficiency in the use of solar radiation on photosynthesis. In the cultivation of seasonal crops of cereals group, leaf development was initially increased at a rate of exponential growth, but the relatively small size of the initial leaf causes the absorption of solar radiation is relatively low. Further development of leaf area increase was followed by increased absorption of solar light energy (Fig. 90). Development of leaf area halted after the plants start flowering ((Gardner, Pearce, and Mitchell, 1985).
At the beginning of individual plant growth, exponential growth rate and expressed as relative growth rate (LTR). LTR in early plant growth is high, but then will continue to decrease regularly with the LTR can not be used as a crop in the field, but can be applied to the assessment of plant growth rate in the first few weeks of plant growth. 

Subsequent plant growth will result in the leaves of the plants will shade each other so ineffective sebahagian leaf photosynthesis. In 1947, Watson introduced the concept of leaf area as a measure of productive crops on cultivated plants called Lear Area Index (LAI) or leaf area index (LAI). ILD crops increased from zero at the beginning of growth and reached its peak in mid-age of the plant, then declined sharply at the phase of aging. Before the decline in middle age plants ILD, ILD is relatively constant because of the balance between the rate of leaf senescence and the rate of formation of new leaves. ILD is generally highest in crops planted at a distance of about 5.0 are common. The highest LAI value of the researchers on corn between 3.9 to 5.0, the peanuts from 4 to 4.5 and 7.0 on cassava (Goldsworthy and Fisher, 1984). 

Canopy of plants that have a high value of ILD in young leaves. At the canopy top has a high rate of CO2 and translocate sebahagian asimilat to actively growing plant parts. The increase in dry weight of leaf area per time unity is called unit leaf rate or net assimilation rate (LAN). The rate of leaf or LAN unit is a measure of the average net CO2 exchange per unit leaf area in the plant canopy, the LAN can be viewed as a measure of the efficiency of photosynthesis per leaf area through increased growth. phases of plant growth is a phase difference of potential photosynthesis of a plant that is actually given by the ILD, so that the LAN is expected to influence the environment during different periods of plant life.