Cane-type plants

Plants of the other type (C4), such as tall tropical grass (maize, sugar cane, millet, sorgo), assimilate C02 from the atmosphere independently of 02 concentration, so that T remains practically constant and at a low level =5 mmol mol-1. These plants react weakly to changes in the concentrations of carbon dioxide. 

These types produce fruit on canes that appeared the previous year. In midsummer, cut down the original cane (there s usually just one per plant) to ground level. Thin out new shoots to about three to six per plant to prevent overcrowding. 

Stable isotope ratio analysis (SIRA, GC-IRMS [Gas Chromatography-Isotope Ratio Mass Spectrometry], and Site Specific Isotope Fractionation — Nuclear Magnetic Resonance [SNIF-NMR]) have proven useful in many adulteration situations. In nature, and exist at relative proportions of 1.11 98.89 [27]. The photosynthetic process selectively enriches the plant in dependent upon the type of photosynthetic process used by the plant. Plants using the Hatch-Slack pathway (e.g., com, sugar cane, millet, and lemon grass) give 8 C values the closest to the standard, i.e., 5 C values of ca. -10. The 5 C value is calculated as ... 

Massoilactone (45) is the major component of the bark oil of Cryptocarya massoia (Lauraceae) (1, 74). The absolute configuration of (-)-massoilactone is (R) at C-5, which is enantiomeric to parasorbic acid (29, 78). An analogous lactone (46) was also isolated from the same plant (22). Massoi bark has been used for many centuries as a constituent of native medicines. The sedative action expected from the structural similarity between massoilactone and active Kawa-type lactones is dubious (9). (-)-Massoilactone has been isolated from cane molasses as one of, and the most characteristic, sugary-flavor substances (48). This compound was also obtained from two species of formicine ants of the genus Cam-ponotus (22). This powerful skin-irritating compound might be responsible for the defensive factor secreted by the ants. 

Some plants, such as corn and sugar cane, have evolved an auxiliary C4-dicarboxylic acid cycle< > that cooperates with the reductive pentose cycle in the photosynthetic assimilation of CO2. In plants with this cycle (sometimes referred to as the Hatch and Slack cycle), chloroplasts in the mesophyll cells near the surface on the leaf contain three C4-pathway specific enzymes pyruvate, phosphate-dikinase that directly converts pyruvate into phosphoenolpyruvate (PEP) with ATP, PEP carboxylase that catalyzes the carboxyla-tion of PEP to oxaloacetate, and malate dehydrogenase that finally reduces oxaloacetate to malate with NADPH. The purpose of these steps is apparently to incorporate CO2 and NADPH into malate in order to translocate them to the vascular bundle sheath cells, where they are again released by the action of a NADP-dependent malic enzyme. The malic enzyme is located in the bundle sheath chloroplasts together with the en mes of the Calvin cycle. CO2 is then reduced to carbohydrates while pyruvate is presumably transported back to the mesophyll cells. Besides the malate-type C4-plants, there is a second and larger group of species (aspartate type) that contains little malic enzyme and utilizes aspartate as the COj carrier. 

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